                                Release Notes

===============================================================================
3.6 Series (201x/xx/xx - )
===============================================================================

                       3.6.0 (subaruboshi) 201x/xx/xx

* Version 3.6.0

    This is the first version of pgpool-II 3.6 series.
    That is, a "major version up" from 3.5 series.

* Overview

    Major enhancements in Pgpool-II 3.6 include:

    - Improve the behavior of fail-over. In the steaming replication mode,
      client sessions will not be disconnected when a fail-over occurs any
      more if the session does not use the failed standby server. If the
      primary server goes down, still all sessions will be disconnected.
      Also it is possible to connect to Pgpool-II even if it is doing health
      checking retries. Before all attempt of connecting to Pgpool-II failed
      while doing health checking retries.

    - New PGPOOL SET command has been introduced. Certain configuration
      parameters now can be changed on the fly in a session.

    - Watchdog is significantly enhanced. It becomes more reliable than
      previous releases.

    - Handling of extended query protocol (e.g. used by Java applications)
      in streaming replication mode speeds up if many rows are returned
      in a result set.

    - Import parser of PostgreSQL 9.6.

    - In some cases pg_terminate_backend() now does not trigger a fail-over.

    - Change documentation format from raw HTML to SGML.

    The above items are explained in more detail in the sections below.

* Major Enhancements

    - Improve the behavior of fail-over. (Tatsuo Ishii)

      In the steaming replication mode, client sessions will not be
      disconnected when a fail-over occurs any more if the session
      does not use the failed standby server. If the primary server
      goes down, still all sessions will be disconnected. Health check
      timeout case will also cause the full session disconnection.
      Other health check error, including retry over case does not
      trigger full session disconnection.

      For user's convenience, "show pool_nodes" command shows the session
      local load balance node info since this is important for users in
      case of fail-over. If the load balance node is not the failed node,
      the session will not be affected by fail-over.

      Also now it is possible to connect to Pgpool-II even if it is doing
      health checking retries. Before all attempt of connecting to Pgpool-II
      failed while doing health checking retries. Before any attempt to
      connect to Pgpool-II fails if it is doing a health check against
      failed node even if fail_over_on_backend_error is off because Pgpool-II
      child first tries to connect to all backend including the failed one and
      exits if it fails to connect to a backend (of course it fails). This is
      a temporary situation and will be resolved before pgpool executes fail-over.
      However if the health check is retrying, the temporary situation keeps longer
      depending on the setting of health_check_max_retries and health_check_retry_
      delay. This is not good. Attached patch tries to mitigate the problem:

      When an attempt to connect to backend fails, give up connecting to
      the failed node and skip to other node, rather than exiting the process
      if operating in streaming replication mode and the node is not primary node.

      Mark the local status of the failed node to "down". This will let the primary
      node be selected as a load balance node and every queries will be sent to the
      primary node. If there's other healthy standby nodes, one of them will be
      chosen as the load balance node.

      After the session is over, the child process will suicide to not retain
      the local status.

    - Add PGPOOL SHOW, PGPOOL SET and PGPOOL RESET commands. (Muhammad Usama)

      These are similar to the PostgreSQL's SET and SHOW commands for GUC
      variables, adding the functionality in Pgpool-II to set and reset
      the value of config parameters for the current session, and for
      that it adds a new syntax in Pgpool-II which is similar to PostgreSQL's
      SET and RESET variable syntax with an addition of PGPOOL keyword at the start.

      Currently supported configuration parameters by PGPOOL SHOW/SET/RESET are:
      log_statement, log_per_node_statement, check_temp_table, check_unlogged_
      table, allow_sql_comments, client_idle_limit, log_error_verbosity,
      client_min_messages, log_min_messages, client_idle_limit_in_recovery.

    - Sync inconsistent status of PostgreSQL nodes in Pgpool-II instances
      after restart. (Muhammad Usama)

    - At the Pgpool-II startup, the status of each configured backend node
      is loaded from the backend status file or otherwise initialized by
      querying the backend nodes. This technique works fine in stand alone mode
      and also with the watchdog enabled as long as the status of backend nodes
      remains consistent until all Pgpool-II nodes got up and running. But since
      Pgpool-II does not sync the backend node status from the watchdog cluster
      at startup time, so in some cases the Pgpool-II nodes participating in the
      watchdog cluster may get a different status for the same backend,
      especially if the Pgpool-II nodes part of the watchdog cluster starts
      at different times and between that time an unavailable backend
      PostgreSQL node had become available again.

      So to solve this, the commit implements the new startup procedure
      for the standby Pgpool-II, And now the standby Pgpool-II will load the
      backend status of all configured PostgreSQL nodes from the watchdog
      master/coordinator node at the time of startup.

    - Enhance performance of SELECT when lots of rows involved. (Tatsuo Ishii)

      Pgpool-II flushes data to network (calling write(2)) every time it
      sends a row data ("Data Row" message) to frontend. For example, if 10,000
      rows needed to be transfer, 10,000 times write()s are issued. This is
      pretty expensive. Since after repeating to send row data, "Command Complete"
      message is sent, it's enough to issue a write() with the command complete
      message. Also there are unnecessary flushing are in handling the command
      complete message.

      Quick testing showed that from 47% to 62% performance enhancements
      were achieved in some cases.

      Unfortunately, performance in workloads where transferring few rows,
      will not be enhanced since such rows are needed to flush to network anyway.

    - Import PostgreSQL 9.6's SQL parser. (Bo Peng)

      This allows Pgpool-II to fully understand the newly added SQL syntax
      such as COPY INSERT RETURNING.

    - In some cases pg_terminate_backend() now does not trigger a fail-over. (Muhammad Usama)

      Since the pg_terminate_backend function in PostgreSQL is used to terminate
      the backend connection, So what happens is, when this function kills a PostgreSQL
      backend that is connected to the Pgpool-II, This disconnection of backend by
      pg_terminate_backend function is appeared as a backend node failure to the
      Pgpool-II. But the problem here is, PostgreSQL does not give any information
      to the client program that the connection is going to be killed because of
      the pg_terminate_backend call and on the client side, it looks similar to
      the backend node failure.

      Now to solve this in Pgpool-II we need two things. First is to
      identify the pg_terminate_backend function in the query and the
      Pgpool-II child process that hosts the particular backend connection
      which will be killed by that pg_terminate_backend function call,
      so that we get a heads up in advance about the backend termination,
      and secondly the routing of the query containing pg_terminate_backend
      also needs a new logic so that the query should be sent to the correct
      PostgreSQL node that hosts the backend with the PID referred by
      the pg_terminate_backend()

      So how does this commit handles pg_terminate_backend()??
      In the SimpleQuery() function which is the work horse of simple query
      processing in the Pgpool-II we start with the search of the
      pg_terminate_backend() function call in the query parse tree and if
      the search comes out to be successful, the next step is to locate
      the Pgpool-II child process and a backend node of that connection
      whose PID is specified in pg_terminate_backend function's argument.
      Once the connection and the Pgpool-II child process is identified,
      we just set the swallow_termination flag(added by this commit in
      ConnectionInfo structure) for that connection in the shared memory,
      and also set the query destination node to the backend node that
      hosts that particular connection and does not call pool_where_to_send()
      for this query so that the query should be sent to the correct
      backend node.

      Now when the query is routed to the correct node and consequently
      the backend gets killed, that results in the communication error on
      Pgpool-II side, the Pgpool-II already knows that this disconnection
      is due the pg_terminate_backend and not because of node failure as
      the swallow_termination flag is already set for the connection.

      Some works are still remaining.

      pg_terminate_backend is not handled with extended query protocol.

      Currently we only support pg_terminate_backend(constant number)
      function calls. If the expression or sub query is used in the
      argument of pg_terminate_backend then it would not be handled e.g

        pgpool=# select pg_terminate_backend(1025);         -- Supported
        pgpool=# select pg_terminate_backend( 2 +1);        -- NOT SUPPORTED
        pgpool=# select pg_terminate_backend((select 1));   -- NOT SUPPORTED

	  Currently only one pg_terminate_backend call in a query is handled.

    - HTML documents are now generated from SGML documents.
      (Muhammad Usama, Tatsuo Ishii, Bo Peng)

      It is intended to have better construction, contents and
      maintainability. However, still there's tremendous room to
      enhance the SGML documents. Please help us!

* Other Enhancements

    - Make authentication error message more user friendly. (Tatsuo Ishii)

      When attempt to connect to backend (including health checking),
      emit error messages from backend something like "sorry,
      too many clients already" instead of "invalid authentication
      message response type, Expecting 'R' and received '%c'"

    - Tighten up health check timer expired condition in pool_check_fd().
      (Muhammad Usama)

      Check if the signal was actually the health check timer expire to
      make sure that we do not declare the timer expire due to some other
      signal arrived while waiting for data for health check in pool_check_fd().

    - Add new script called "watchdog_setup". (Tatsuo Ishii)

      watchdog_setup is a command to create a temporary installation
      of Pgpool-II clusters with watchdog for mainly testings.

      Add "-pg" option to pgpool_setup. (Tatsuo Ishii)

      This is useful when you want to assign specific port numbers to
      PostgreSQL while using pgpool_setup. Also now pgpool_setup is
      installed in the standard bin directory which is same as pgpool.

    - Add "replication delay" column to "show pool_nodes". (Tatsuo Ishii)

      This column shows the replication delay value in bytes if operated
      in streaming replication mode.

    - Do not update status file if all backend nodes are in down
      status. (Chris Pacejo, Tatsuo Ishii)

      This commit tries to remove the data inconsistency in replication
      mode found in [pgpool-general: 3918] by not recording the status file
      when all backend nodes are in down status. This surprisingly simple
      but smart solution was provided by Chris Pacejo.

    - Allow to use multiple SSL cipher protocols. (Multiple Usama)

      By replacing TLSv1_method() with SSLv23_method() while initializing
      the SSL session, we can use more protocols than TLSv1 protocol.

      Allow to use arbitrary number of items in the
      black_function_list/white_function_list. (Muhammad Usama)

      Previously there were fixed limits for those.

    - Properly process empty queries (all comments). (Tatsuo Ishii)

      Pgpool-II now recognizes an empty query consisted of all comments
      (for example "/* DBD::Pg ping test v3.5.3 */") (note that no ';')
      as an empty query.

      Before such that query was recognized an error.

      Add some warning messages for wd_authkey hash calculation
      failure. (Yugo Nagata)

      Sometimes wd_authkey calculation fails for some reason other
      than authkey mismatch. The additional messages make these distinguishable
      for each other.

* Changes

    - Change the default value of search_primary_node_timeout from 10 to
      300. (Tatsuo Ishii)

      Prior default value 10 seconds is sometimes too short for a standby
      to be promoted.

    - Change the Makefile under directory src/sql/, that is proposed by
       [pgpool-hackers: 1611]. (Bo Peng)

    - Change the PID length of pcp_proc_count command output to 6
      characters long. (Bo Peng)

      If the Pgpool-II process ID are over 5 characters, the 6th character
      of each process ID will be removed. This commit changes the process ID
      length of pcp_proc_count command output to 6 characters long.

    - Redirect all user queries to primary server. (Tatsuo Ishii)

      Up to now some user queries are sent to other than the primary
      server even if load_balance_mode = off. This commit changes the
      behavior: if load_balance_mode = off in streaming replication mode,
      now all the user queries are sent to the primary server only.

* Bug fixes

    - Fix the case when all backends are down then 1 node attached. (Tatsuo Ishii)

      When all backends are down, no connection is accepted. Then 1
      PostgreSQL becomes up, and attach the node using pcp_attach_node.
      It successfully finishes. However, when a new connection arrives,
      still the connection is refused becausePgpool-II child process
      looks into the cached status, in which the recovered node is
      still in down status if mode is streaming replication mode
      (native replication and other modes are fine). Solution is,
      if all nodes are down, force to restart all pgpool child.

    - Fix for avoiding downtime when Pgpool-II changes require a
      restart. (Muhammad Usama)

      To fix this, The verification mechanism of configuration
      parameter values is reversed, previously the standby nodes used
      to verify their parameter values against the respective values
      on the master Pgpool-II node and when the inconsistency was
      found the FATAL error was thrown, now with this commit the
      verification responsibility is delegated to the master Pgpool-II
      node. Now the master node will verify the configuration parameter
      values of each joining standby node against its local values and
      will produce a WARNING message instead of an error in case of a
      difference. This way the nodes having the different configurations
      will also be allowed to join the watchdog cluster and the user
      has to manually look out for the configuration inconsistency
      warnings in the master Pgpool-II log to avoid the surprises at
      the time of Pgpool-II master switch over.

    - Fix a problem with the watchdog failover_command locking mechanism. (Muhammad Usama)

      From Pgpool-II 3.5 watchdog was using the separate individual
      locks for each node-failover command (failover, failback and follow-master)
      and the lock was acquired just before executing the respective failover
      script and was released as soon as the script execution finishes.
      This technique although was very efficient but also had a problem.
      If the failover_command takes a very little time and gets finished
      before the lock request from other Pgpool-II node arrives, the other
      node is also granted a lock, since the lock was already released by
      the first node at that time. Consequently, both nodes ends up executing
      the failover script. So to fix this we are reverting back to the tested
      failover interlocking design used prior to Pgpool-II 3.5 where all the
      commands gets locked at the failover start by the node that becomes a
      lock-holder and each command lock is released after its execution
      finishes. And only the lock-holder node is allowed to acquire/release
      the individual command lock. That way the lock-holder node keeps the
      lock-holder status throughout the span of the failover execution and
      the system becomes less time sensitive.

    - Disable strict aliasing optimization. (Tatsuo Ishii)

      flatten_set_variable_args() was imported from PostgreSQL in Pgpool-II 3.5.
      To make the code work, a compiler flag -fno-strict-aliasing is necessary
      (PostgreSQL does so). Unfortunately when the function was imported, the
      compiler flag was not added. To fix this, configure.ac was modified.

    - Do not use random() while generating MD5 salt. (Tatsuo Ishii)

      random() should not be used in security related applications.
      To replace random(), import PostmasterRandom() from PostgreSQL.
      Also store current time at the start up of Pgpool-II main process
      for later use.

    - Don't ignore sync message from frontend when query cache is enabled. (Tatsuo Ishii)

      While returning cached query result, sync message sent from frontend
      is discarded. This is harmless because "ready for query" messages is
      sent to frontend afterward. Problem is, AccessShareLock held by previous
      parse message processing is not released until sync message is received
      by the backend. Fix is, forwarding the sync message to backend and discarding
      "ready for query" message returned from backend.

    - Fix bug that Pgpool-II fails to start if listen_addresses is
      empty string. (bug 237) (Muhammad Usama)

      The socket descriptor array (fds[]) was not getting the array
      end marker when TCP listen addresses are not used.

    - Create regression log directory if it does not exist yet. (Tatsuo Ishii)

    - Fixing the error messages when the socket operation fails. (Muhammad Usama)

      When some socket operation fails, we issue close socket before throwing
      an error which causes the errno value to be overwritten and consequently
      the error log does not print the correct failure reason. The solution is
      to save the errno before closing the socket and use the saved value to
      print error description.

    - Fix regression failure of 003.failover. (Tatsuo Ishii)

      Update expected data to reflect the changes made to show pool_nodes.
      Also fix show pool_nodes to proper use "_" instead of space for the
      column name.

    - Fix hang when portal suspend received. (bug 230) (Tatsuo Ishii)

      When portal suspend message is received, it's not enough to forward it
      to the client. Since backend expects to receive execute message, trying
      to read further more messages from backend will never succeed.
      To fix this, turn off the query in progress flag, which will pole
      incoming message from the client.

    - Fix pgpool doesn't de-escalate IP in case network restored. (bug 228) (Muhammad Usama)

      set_state function is made to de-escalate, when it is changing the
      local node's state from the coordinator state to some other state.

    - SIGUSR1 signal handler should be installed before watchdog
      initialization. (Muhammad Usama)

      Since there can be a case where a failover request from other
      watchdog nodes arrive at the same time when the watchdog has just
      been initialized, and if we wait any longer to install a SIGUSR1
      signal handler, it can result in a potential crash

    - Fix for bug of inconsistent status of PostgreSQL nodes in
      Pgpool-II instances after restart. (bug 218) (Muhammad Usama)

      Watchdog does not synchronize status. Currently at the Pgpool-II
      startup, The status of each configured backend node is loaded from the
      backend status file or otherwise initialized by querying the backend
      nodes. This technique works fine in stand alone mode and also with
      the watchdog enabled as long as the status of backend nodes remains
      consistent until all Pgpool-II nodes got up and running. But since
      Pgpool-II does not sync the backend node status from the watchdog
      cluster at startup time, so in some cases the pgpool-II nodes
      participating in the watchdog cluster may get a different status
      for the same backend, especially if the Pgpool-II nodes part of
      the watchdog cluster starts at different times and between that
      time an unavailable backend PostgreSQL node had become available
      again.

      So to solve this, the commit implements the new startup procedure
      for the standby Pgpool-II, And now the standby Pgpool-II will
      load the backend status of all configured PostgreSQL nodes from
      the watchdog master/coordinator node at the time of startup.

    - Fix Pgpool-II doesn't escalate ip in case of another node
      unavailability. (bug 215) (Muhammad Usama)

      The heartbeat receiver fails to identify the heartbeat sender watchdog
      node when the heartbeat destination is specified in terms of an IP address
      while wd_hostname is configured as a hostname string or vice versa.

    - Fixing a coding mistake in watchdog code. (Muhammad Usama)

      wd_issue_failover_lock_command() function is supposed to forward
      command type passed in as an argument to the wd_send_failover_sync_command()
      function instead it was passing the NODE_FAILBACK_CMD command type.

      The commit also contains some log message enhancements.

    - Display human readable output for backend node status. (Muhammad Usama)

      Changed the output of pcp_node_info utility and show commands display
      human readable backend status string instead of internal status code.

    - Replace "MAJOR" macro to prevent occasional failure. (Tatsuo Ishii)

      The macro calls pool_virtual_master_db_node_id() and then access
      backend->slots[id]->con using the node id returned. In rare cases,
      it could point to 0 (in case when the DB node is not connected),
      which gives access to con->major, then it causes a segfault.

    - Fix "kind mismatch" error message in Pgpool-II. (Muhammad Usama)

      Many of "kind mismatch..." errors are caused by notice/warning messages
      produced by one or more of the DB nodes. In this case now Pgpool-II forwards
      the messages to frontend, rather than throwing the "kind mismatch..." error.
      This would reduce the chance of "kind mismatch..." errors.

    - Fix handling of pcp_listen_addresses config parameter. (Muhammad Usama)

    - Save and restore errno in each signal handler. (Tatsuo Ishii)

    - Fix usage of wait(2) in pgpool main process. (Tatsuo Ishii)

      When child process dies, SIGCHLD signal is raised and wait(2) knows
      the event. However, multiple child death does not necessarily creates exact
      same number of SIGCHLD signal as the number of dead children and wait(2)
      could wait for an event which never happens in this case. I Actually
      encountered this situation while testing Pgpool-II. Solution is,
      to use waitpid(2) instead of wait(2).

    - Fix confusing error messages. (Tatsuo Ishii)

      pool_read() does not emit error messages when read(2) returns -1
      if fail_over_on_backend_error is off. In any case the cause of error
      should be emitted. I do not back port this because it's a too trivial
      enhancement.

    - Fix buffer over run problem in "show pool_nodes". (Tatsuo Ishii)

      While processing "show pool_nodes", the buffer for hostname was too short.
      It should be same size as the buffer used for pgpool.conf. Problem reported
      by a twitter user who is using pgpool on AWS (which could have very long hostname).

    - Fix [pgpool-hackers: 1638] pgpool-II does not use default configuration. (Muhammad Usama)

      Configuration file not found should just throw a WARNING message
      instead of ERROR or FATAL.

    - Fix bug with load balance node id info on shmem. (Tatsuo Ishii)

      There are few places where the load balance node was mistakenly
      put on wrong place. It should be placed on:

            ConnectionInfo *con_info[child id, connection pool_id, backend id].load_balancing_node].

      In fact it was placed on:

            *con_info[child id, connection pool_id, 0].load_balancing_node].


      As long as the backend id in question is 0, it is ok. However while
      testing Pgpool-II 3.6's enhancement regarding failover,
      if primary node is 1 (which is the load balance node) and standby
      is 0, a client connecting to node 1 is disconnected when failover
      happens on node 0. This is unexpected and the bug was revealed.

      It seems the bug was there since long time ago but it had
      not found until today by the reason above.

    - Fix for bug that pgpool hangs connections to database. (bug 197) (Muhammad Usama)

      The client connection was getting stuck when backend node and
      remote Pgpool-II node becomes unavailable at the same time.
      The reason was a missing command timeout handling in the function
      that sends the IPC commands to watchdog.

    - Fix a possible hang during health checking. (bug 204) (Yugo Nagata)

      Health checking was hang when any data wasn't sent from
      backend after connect(2) succeeded. To fix this, pool_check_fd()
      returns 1 when select(2) exits with EINTR due to SIGALRM while
      health checking is performed.

    - Deal with the case when the primary is not node 0 in streaming
      replication mode. (Tatsuo Ishii)

      http://www.pgpool.net/mantisbt/view.php?id=194#c837 reported that
      if primary is not node 0, then statement timeout could occur even
      after bug194-3.3.diff was applied. After some investigation,
      it appeared that MASTER macro could return other than primary
      or load balance node, which was not supposed to happen,
      thus do_query() sends queries to wrong node (this is not clear
      from the report but I confirmed it in my investigation).

      pool_virtual_master_db_node_id(), which is called in MASTER macro
      returns query_context->virtual_master_node_id if query context exists.
      This could return wrong node if the variable has not been set yet.
      To fix this, the function is modified: if the variable is not either
      load balance node or primary node, the primary node id is returned.

      For master and 3.5-stable, additional fixes/enhancements are made:
      pool_extended_send_and_wait() now issues flush message if the request
      is 'E' (execute).
      Before it was issued outside (in Execute), but this makes the logic to
      determine to which node the flush message to be sent unnecessary complex.

      A debug message in pool_write is enhanced by adding backend node id.

    - If statement timeout is enabled on backend and do_query() sends a query to
      primary node, and all of following user queries are sent to standby,
      it is possible that the next command, for example END, could cause a statement
      timeout error on the primary, and a kind mismatch error on pgpool-II is
      raised. (bug 194) (Tatsuo Ishii)

      This fix tries to mitigate the problem by sending sync message instead of
      flush message in do_query(), expecting that the sync message reset the
      statement timeout timer if we are in an explicit transaction.
      We cannot use this technique for implicit transaction case, because
      the sync message removes the unnamed portal if there's any.

      Plus, pg_stat_statement will no longer show the query issued
      by do_query() as "running".

    - Fix extended protocol handling in raw mode. (Tatsuo Ishii)

      Bug152 reveals that extended protocol handling in raw mode
      (actually other than in stream mode) was wrong in Describe()
      and Close(). Unlike stream mode, they should wait for backend response.

    - Fix confusing comments in pgpool.conf. (Tatsuo Ishii)

    - Fix Japanese and Chinese documentation bug about raw mode. (Yugo Nagata, Bo Peng)

      Connection pool is available in raw mode.

    - Fix is_set_transaction_serializable() when
      SET default_transaction_isolation TO 'serializable'. (bug 191) (Bo Peng)

      SET default_transaction_isolation TO 'serializable' is sent to not only
      primary but also to standby server in streaming replication mode,
      and this causes an error. Fix is, in streaming replication mode,
      SET default_transaction_isolation TO 'serializable' is sent only to
      the primary server.

    - Fix extended protocol hang with empty query. (bug 190) (Tatsuo Ishii)

      The fixes related to extended protocol cases in 3.5.1 broke the case of
      empty query. In this case backend replies with "empty query response"
      which is same meaning as a command complete message. Problem is, when
      empty query response is received, pgpool does not reset the query in progress
      flag thus keeps on waiting for backend. However, backend will not send the
      ready for query message until it receives a sync message. Fix is,
      resetting the in progress flag after receiving the empty query response
      and reads from frontend expecting it sends a sync message.

    - Fix for [pgpool-general: 4569] Pgpool-II 3.5 : segfault. (Muhammad Usama)

      PostgreSQL's memory and exception manager APIs adopted by the Pgpool-II 3.4
      are not thread safe and are causing the segmentation fault in the watchdog
      lifecheck process, as it uses the threads to ping configured trusted hosts for
      checking the upstream connections. Fix is to remove threads and use the child
      process approach instead.

    - Validating the PCP packet length. (Muhammad Usama)

      Without the validation check, a malformed PCP packet can crash the
      PCP child and/or can run the server out of memory by sending the packet
      with a very large data size.

    - Fix Pgpool-II hang bug (bug 167). (Tatsuo Ishii)

      Pgpool-II 3.5 or after in streaming replication mode does not
      wait for response from each phase such parse, bind anymore.
      However, if do_query is called, it sends flush message to retrieve
      the result of system catalog look up. This is only sent to primary node
      which may results in retrieving previous message results, for example
      parse complete. If standby is assigned to load balance node, the node
      does not return parse complete message, which will cause a problem
      in bug167 case, because parse message for "BEGIN" was sent to both the
      primary and the standby. Fix is, send flush message in do_query if the
      load balance node is one of standbys.

    - Fix pgpool_setup to not confuse log output. (Tatsuo Ishii)

      Before it simply redirects the stdout and stderr of pgpool process
      to a log file. This could cause log contents being garbled or even
      missed because of race condition caused by multiple process being
      writing concurrently. I and Usama found this while investigating
      the regression failure of 004.watchdog. To fix this, pgpool_setup
      now generates startall script so that pgpool now sends stdout/stderr
      to cat command and cat writes to the log file (It seems the race
      condition does not occur when writing to a pipe).

    - Fix for [pgpool-general: 4519] Worker Processes Exit and
      Are Not Re-spawned. (Muhammad Usama)

      The problem was due to a logical mistake in the code for checking
      the exiting child process type when the watchdog is enabled.
      I have also changed the severity of the message from FATAL to LOG,
      emitted for child exits due to max connection reached.

    - Fix pgpool hung after receiving error state from backend. (bug #169) (Tatsuo Ishii)

      This could happen if we execute an extended protocol query
      and it fails. After an error is received the "ignore till sync flag"
      is set and retained even if sync message was actually received.
      Thus any subsequent query (in the case above "DEALLOCATE message")
      is not processed and pgpool waits for message from frontend and backend,
      and pgpool sticks here because no message will arrive from both side.

      To fix this, unconditionally reset the "ignore till sync flag"
      in ReadyforQuery(). This is safe because apparently we already
      received the ready for query message.

    - Fix query stack problems in extended protocol case. (bug 167, 168) (Tatsuo Ishii)

    - Fix [pgpool-hackers: 1440] yet another reset query stuck problem. (Tatsuo Ishii)

      After receiving X message from frontend, if Pgpool-II detects EOF
      on the connection before sending reset query, Pgpool-II could wait for
      backend which had not received the reset query. To fix this,
      if EOF received, treat this as FRONTEND_ERROR, rather than ERROR.

    - Fix for [pgpool-general: 4265] another reset query stuck problem. (Muhammad Usama)

      The solution is to report FRONTEND_ERROR instead of simple ERROR
      when pool_flush on front-end socket fails.

    - Fixing pgpool-recovery module compilation issue with PostgreSQL 9.6. (Muhammad Usama)

      Incorporating the change of function signature for GetConfigOption()
      functions in PostgreSQL 9.6

    - Fix compile issue on freebsd. (Muhammad Usama)

      Add missing include files. The patch is contributed by the bug
      reporter and enhanced a little by me.

    - Fix regression test to check timeout of each test. (Yugo Nagata)

    - Add some warning messages for wd_authkey hash calculation failure. (Yugo Nagata)

      Sometimes wd_authkey calculation fails for some reason other
      than authkey mismatch. The additional messages make these distinguishable
      for each other.

===============================================================================
3.5 Series (2016/01/29 - )
===============================================================================

                       3.5.4 (ekieboshi) 2016/08/31

* Version 3.5.4

    This is a bugfix release against pgpool-II 3.5.3.

    __________________________________________________________________

* Bug fixes

    - Fix buffer over run problem in "show pool_nodes". (Tatsuo Ishii)

      While processing "show pool_nodes", the buffer for hostname was too
      short. It should be same size as the buffer used for pgpool.conf.
      Problem reported by a twitter user who is using pgpool on AWS (which
      could have very long hostname).

    - Fix usage of wait(2) in pgpool main process. (Tatsuo Ishii)

      The usage of wait(2) in pgpool main could cause infinite wait in the
      system call. Solution is, to use waitpid(2) instead of wait(2).

    - Save and restore errno in each signal handler. (Tatsuo Ishii)

    - Fix handling of pcp_listen_addresses config parameter. (Muhammad Usama)

    - Fix "kind mismatch" error message in pgpool. (Muhammad Usama)

      Many of "kind mismatch..." errors are caused by notice/warning
      messages produced by one or more of the DB nodes. In this case now
      Pgpool-II forwards the messages to frontend, rather than throwing the
      "kind mismatch..." error. This would reduce the chance of "kind
      mismatch..."  errors.

      See [pgpool-hackers: 1501] for more details.

    - Replace "MAJOR" macro to prevent occasional failure. (Tatsuo Ishii)

      The macro calls pool_virtual_master_db_node_id() and then access
      backend->slots[id]->con using the node id returned.  In rare cases, it
      could point to 0 (in case when the DB node is not connected), which
      gives access to con->major, then it causes a segfault.

      See bug 225 for related info.

    - Fixing a coding mistake in watchdog code. (Muhammad Usama)

      wd_issue_failover_lock_command() function is supposed to forward command type
      passed in as an argument to the wd_send_failover_sync_command() function instead
      it was passing the NODE_FAILBACK_CMD command type.

      The commit also contains some log message enhancements.

    - doc : Fixing a typo in english doc (Muhammad Usama)

    - Fix for bun 215 that pgpool doesn't escalate ip in case of another node unavailability.
      (Muhammad Usama)

      The heartbeat receiver fails to identify the heartbeat sender watchdog node when
      the heartbeat destination is specified in terms of an IP address while
      wd_hostname is configured as a hostname string or vice versa.

      See bug 215 for related info.

    - Fix for bug of inconsistent status of Postgresql nodes in Pgpool instances
      after restart.(Muhammad Usama)

      Watchdog does not synchronize status.

      See bug 218 for related info.

    - SIGUSR1 signal handler should be installed before watchdog initialization.
      (Muhammad Usama)

      Since there can be a case where a failover request from other watchdog nodes
      arrive at the same time when the watchdog has just been initialized,
      and if we wait any longer to install a SIGUSR1 signal handler, it can
      result in a potential crash.

    - Fix for bug 228 that pgpool doesn't de-escalate IP in case network restored.
      (Muhammad Usama)

      See bug 228 for related info.

    - Fix hang when portal suspend received. (Tatsuo Ishii)

      See bug 230 for related info.

    - test : Add regression test for bug 230. (Tatsuo Ishii)

    - Fixing a typo in the log message. (Muhammad Usama)

    - Fixing the error messages when the socket operation fails. (Muhammad Usama)

    - Tighten up health check timer expired condition in pool_check_fd(). (Muhammad Usama)

    - doc : Add comment to the document about connection_cache. (Tatsuo Ishii)

    - Fix Handling of pcp_socket_dir was missing from pool_get_config(). (Muhammad Usama)

    - doc : Fix Japanese document typo. (Bo Peng)

    - Fix "out of memory" by using "pg_md5 -m".(Muhammad Usama)

      See bug 236 for related info.

    - Fix for 237 that Pgpool-II fails to start if listen_addresses is empty string.
      (Muhammad Usama)

      The socket descriptor array (fds[]) was not getting the array end marker
      when TCP listen addresses are not used.

      See bug 237 for related info.

===============================================================================

                        3.5.3 (ekieboshi) 2016/06/17

* Version 3.5.3

    This is a bugfix release against pgpool-II 3.5.2.

    __________________________________________________________________

* New features

    - Allow to access to pgpool while doing health checking (Tatsuo Ishii)

      Currently any attempt to connect to pgpool fails if pgpool is doing
      health check against failed node even if fail_over_on_backend_error is
      off because pgpool child first tries to connect to all backend
      including the failed one and exits if it fails to connect to a backend
      (of course it fails). This is a temporary situation and will be
      resolved before pgpool executes failover. However if the health check
      is retrying, the temporary situation keeps longer depending on the
      setting of health_check_max_retries and health_check_retry_delay. This
      is not good. Attached patch tries to mitigate the problem:

      - When an attempt to connect to backend fails, give up connecting to
        the failed node and skip to other node, rather than exiting the
        process if operating in streaming replication mode and the node is
        not primary node.

      - Mark the local status of the failed node to "down".

      - This will let the primary node be selected as a load balance node
        and every queries will be sent to the primary node. If there's other
        healthy standby nodes, one of them will be chosen as the load
        balance node.

      - After the session is over, the child process will suicide to not
        retain the local status.

      Per [pgpool-hackers: 1531].

* Bug fixes

    - Fix is_set_transaction_serializable() when
      SET default_transaction_isolation TO 'serializable'. (Bo Peng)

      SET default_transaction_isolation TO 'serializable' is sent to
      not only primary but also to standby server in streaming replication mode,
      and this causes an error. Fix is, in streaming replication mode,
      SET default_transaction_isolation TO 'serializable' is sent only to the
      primary server.

      See bug 191 for related info.

    - Fix Chinese documentation bug about raw mode (Yugo Nagata, Bo Peng)
      Connection pool is available in raw mode.

    - Fix confusing comments in pgpool.conf (Tatsuo Ishii)

    - Fix extended protocol handling in raw mode (Tatsuo Ishii)

      Bug152 reveals that extended protocol handling in raw mode (actually
      other than in stream mode) was wrong in Describe() and Close().
      Unlike stream mode, they should wait for backend response.

      See bug 152 for related info.

    - Permit pgpool to support multiple SSL cipher protocols (Muhammad Usama)

      Currently TLSv1_method() is used to initialize the SSL context, that puts an
      unnecessary limitation to allow only TLSv1 protocol for SSL communication.
      While postgreSQL supports other ciphers protocols as well. The commit changes
      the above and initializes the SSLSession using the SSLv23_method()
      (same is also used by PostgreSQL). Because it can negotiate the use of the
      highest mutually supported protocol version and remove the limitation of one
      specific protocol version.

    - If statement timeout is enabled on backend and do_query() sends a (Tatsuo Ishii)
      query to primary node, and all of following user queries are sent to
      standby, it is possible that the next command, for example END, could
      cause a statement timeout error on the primary, and a kind mismatch
      error on pgpool-II is raised.

      This fix tries to mitigate the problem by sending sync message instead
      of flush message in do_query(), expecting that the sync message reset
      the statement timeout timer if we are in an explicit transaction. We
      cannot use this technique for implicit transaction case, because the
      sync message removes the unnamed portal if there's any.

      Plus, pg_stat_statement will no longer show the query issued by
      do_query() as "running".

      See bug 194 for related info.

    - Deal with the case when the primary is not node 0 in streaming replication mode.
      (Tatsuo Ishii)

      http://www.pgpool.net/mantisbt/view.php?id=194#c837 reported that if
      primary is not node 0, then statement timeout could occur even after
      bug194-3.3.diff was applied. After some investigation, it appeared
      that MASTER macro could return other than primary or load balance
      node, which was not supposed to happen, thus do_query() sends queries
      to wrong node (this is not clear from the report but I confirmed it in
      my investigation).

      pool_virtual_master_db_node_id(), which is called in MASTER macro
      returns query_context->virtual_master_node_id if query context
      exists. This could return wrong node if the variable has not been set
      yet. To fix this, the function is modified: if the variable is not
      either load balance node or primary node, the primary node id is
      returned.

    - Fix a possible hang during health checking (Yugo Nagata)

      Health checking was hang when any data wasn't sent
      from backend after connect(2) succeeded. To fix this,
      pool_check_fd() returns 1 when select(2) exits with
      EINTR due to SIGALRM while health checking is performed.

      Reported and patch provided by harukat and some modification
      by Yugo.

      See bug 204 for related info.

    - change the Makefile under this directory src/sql/,that is proposed by (Bo Peng)
      [pgpool-hackers: 1611]

    - fix for 0000197: pgpool hangs connections to database.. (Muhammad Usama)

      The client connection was getting stuck when backend node and remote pgpool-II
      node becomes unavailable at the same time. The reason was a missing command
      timeout handling in the function that sends the IPC commands to watchdog.

    - Fix bug with load balance node id info on shmem (Tatsuo Ishii)

      There are few places where the load balance node was mistakenly put on
      wrong place. It should be placed on:
      ConnectionInfo *con_info[child id, connection pool_id, backend id].load_balancing_node].
      In fact it was placed on:
      *con_info[child id, connection pool_id, 0].load_balancing_node].

      As long as the backend id in question is 0, it is ok. However while
      testing pgpool-II 3.6's enhancement regarding failover, if primary
      node is 1 (which is the load balance node) and standby is 0, a client
      connecting to node 1 is disconnected when failover happens on node
      0. This is unexpected and the bug was revealed.

      It seems the bug was there since long time ago but it had not found
      until today by the reason above.


    - Fixing coverity scan reported issues. (Muhammad Usama)

===============================================================================

                        3.5.2 (ekieboshi) 2016/04/26

* Version 3.5.2

    This is a bugfix release against pgpool-II 3.5.1.

    __________________________________________________________________

* Bug fixes

    - Fix for segfault during trusted_servers check (Muhammad Usama)

      PostgreSQL's memory and exception manager APIs adopted by the
      pgpool 3.4 are not thread safe and are causing the segmentation fault
      in the watchdog lifecheck process, as it uses the threads to ping
      configured trusted hosts for checking the upstream connections.
      Fix is to remove threads and use the child process approach instead.

      See [pgpool-general: 4569] for more details.

    - Removing the limit on the maximum number of items in the
      black_function_list and white_function_list lists (Muhammad Usama)

      extract_string_tokens in pool_config uses the fixed size malloc on
      the array to hold the black_function_list/white_function_list items.
      This imposes a limit of maximum items in these lists.
      The fix is to use realloc to increase the array size when it gets full.

    - Fix check "PCP Directory" in "Parameter Setting" in install
      (Nozomi Anzai)

      The command "pcp_system_info" was discarded in 3.5, but pgpoolAdmin
      still confirmed if it existed.

      Per bug #187.

    - Fix extended protocol hang with empty query (Tatsuo Ishii)

      The fixes related to extended protocol cases in 3.5.1 broke the case
      of empty query.  In this case backend replies with "empty query
      response" which is same meaning as a command complete message. Problem
      is, when empty query response is received, pgpool does not reset the
      query in progress flag thus keeps on waiting for backend. However,
      backend will not send the ready for query message until it receives a
      sync message. Fix is, resetting the in progress flag after receiving
      the empty query response and reads from frontend expecting it sends a
      sync message.

      Per bug #190.

    - Redirect all user queries to primary server (Tatsuo Ishii)

      Up to now some user queries are sent to other than the primary server
      even if load_balance_mode = off. This commit changes the behavior: if
      load_balance_mode = off in streaming replication mode, now all the
      user queries are sent to the primary server only.

      Per bug #189.

    - Change the PID length of pcp_proc_count command result to 6 characters
      long (Bo Peng)

      If the pgpool process ID are over 5 characters, the 6th character of each
      process ID will be removed. This commit changes the process ID length of
      pcp_proc_count command result to 6 characters long.

      Per bug #188.

===============================================================================

                        3.5.1 (ekieboshi) 2016/04/04

* Version 3.5.1

    This is a bugfix release against pgpool-II 3.5.0.

    __________________________________________________________________

* Bug fixes

    - Add some warning messages for wd_authkey hash calculation failure
      (Yugo Nagata)

      Sometimes wd_authkey calculation fails for some reason other than
      authkey mismatch. The additional messages make these distinguishable
      for each other.

    - test: Fix regression test to check timeout of each test (Yugo Nagata)

    - test: Allow timeout value to be specified by the command option
      (Yugo Nagata)

    - Fix compile issue on FreeBSD (Muhammad Usama)

      Added missing include files.

      Per bug #166. The patch is contributed by the bug reporter and
      enhanced a little by Usama.

    - test: Fix test/regression/clean.sh to remove binary files of
      010.rewrite_timestamp test (Yugo Nagata)

    - Fix memory leak reported by Coverity (CID 1350095) (Yugo Nagata)

    - Fixing pgpool-recovery module compilation issue with PostgreSQL 9.6
      (Muhammad Usama)

      Incorporating the change of function signature for GetConfigOption..()
      functions in PostgreSQL 9.6.

    - Fix to properly process an empty query that has only comments
      (Tatsuo Ishii)

      Pgpool-II recognized an empty query, for example "/* DBD::Pg ping test
      v3.5.3 */" (note that it has no ';') as an error and emits message
      "Unable to parse the query". This is because raw_parser() cannot
      distinguish an empty query from an error query due to the poor API
      design. To fix this new out parameter "*error" added to the
      function. If an error occurred, the variable is set to true and caller
      can know the reason why raw_parser() returns NIL is because of an error
      query or an empty query.

      Per bug #154. See [pgpool-hackers: 1359] for additional information.

    - Fix a reset query stuck problem (Muhammad Usama)

      The solution is to report FRONTEND_ERROR instead of simple ERROR when
      pool_flush on front-end socket fails.

      The original report is
      [pgpool-general: 4265] Pgpool - connection hangs in DISCARD ALL

      The patch was generated by Usama and Pawel Ufnalewski<archon@foap.com>,
      and Gerhard Wiesinger <lists@wiesinger.com> helped to verify and test
      the fix.

    - Fix a reset query stuck problem (Tatsuo Ishii)

      After receiving X message from frontend, if pgpool-II detects EOF on
      the connection before sending reset query, pgpool-II could wait for
      a response from backend which had not received the reset query.
      To fix this, if EOF received, treat this as FRONTEND_ERROR, rather
      than ERROR.

      See "[pgpool-hackers: 1440] Yet another reset query stuck problem"
      for more details.

    - Fix query stuck problems in streaming replication mode with extended
      protocol queries (Tatsuo Ishii)

      This fix is for both bug #167 and #168.

    - Fix pgpool hung after receiving error state from backend (Tatsuo Ishii)

      This could happened if we execute an extended protocol query and it
      fails.

      Per bug #169.

    - Fix bug that child processes exit and are not re-spawned (Muhammad Usama)

      The problem was due to a logical mistake in the code for checking the
      exiting child process type when the watchdog is enabled. Also the severity
      of the message emitted for child exits due to max connection reached
      from FATAL to LOG.

      Per [pgpool-general: 4519] Worker Processes Exit and Are Not Re-spawned

    - Fix typo in configure (Tatsuo Ishii)

      Patch provided by Thomas Munro.

    - doc: Change description of backend_flag (Tatsuo Ishii)

      It is pointed out that restarting pgpool-II is not necessary.

      Per [pgpool-general-jp: 1394].

    - doc: Fix installation procedure. (Tatsuo Ishii)

      With PostgreSQL 9.4 or later, installing pgpool_regclass is not needed.

    - test: Fix pgpool_setup to not confuse log output (Tatsuo Ishii)

      Before it simply redirects stdout and stderr of pgpool processes to
      a log file. This could cause the log contents being garbled or even
      missed because of race condition caused by multiple process being
      writing concurrently.

      To fix this, pgpool_setup now generates startall script in which pgpool
      sends stdout/stderr to cat command by pipe, and cat writes to the log
      file.

    - Fix to validate the PCP packet length (Muhammad Usama)

      Without the validation check, a malformed PCP packet can crash the
      PCP child and/or can run the server out of memory by sending the packet
      with a very large data size.

===============================================================================

                        3.5.0 (ekieboshi) 2016/01/29

* Version 3.5.0

      This is the first version of pgpool-II 3.5 series.
      That is, a "major version up" from 3.4 series.

      __________________________________________________________________

* Incompatible changes

    - Remove parallel query mode codes (Yugo Nagata)

      There are very few users and the maintenance efforts are not worth it.
      Codes for system db are also removed, since this was used in only parallel
      query mode and old query cache on disk.

    - Rename parameter name from ifconfig_path to if_cmd_path (Yugo Nagata)

      ifconfig_path isn't appropriate for the parameter name because
      ifconfig command is obsolete and now ip command is used as default.

    - Change the syntax of pcp commands arguments (Muhammad Usama)

    - Change the output and the argument semantics of pcp_watchdog_info command
      (Muhammad Usama)

      The command is enhanced to show watchdog information about all pgpool-II
      nodes in the cluster. According to this, the argument to specify node index
      is changed so that 0 means local pgpool-II node instead of the first remote
      node.

      __________________________________________________________________

* New features

    - Add new parameter "serialize_accept" (Tatsuo Ishii)

      This parameter defines whether to serialize accept() call for incoming
      client connections.  Default is off, which means no serializing (same
      behavior as pgpool-II 3.4 or before).  If this is off, the kernel
      wakes up all of pgpool-II child process to execute accept() and one of
      them actually accepts the incoming connection.  Problem here is,
      because so my child process wake up at a same time, heavy context
      switching occurred and the performance is affected.  This phenomena is
      a classic problem called "the thundering herd problem".  By enabling
      serialize_accept, only one of pgpool-II child process is woken up and
      executes accept() and the problem can be avoided.

    - Import parser of PostgreSQL 9.5 (Yugo Nagata)

      pgpool-II can understand new syntax introduced in PostgreSQL 9.5 now.
      Especially GROUPING SET, CUBE, ROLLUP and TABLESAMPLE can be be load
      balanced and can be used in query cache (except for TABLESAMPLE).

      Also INSERT...ON CONFLICT and UPDATE tab SET (col1, col2, ...) =
      (SELECT ...) ... can now be properly handled in query rewriting in
      native replication mode.

    - Allow to specify database for health check and streaming replication
      delay check. (Tatsuo Ishii)

      For this purpose new directive "health_check_database" and
      "sr_check_database" are added.

      __________________________________________________________________

* Enhancements

    - Performance improvement in extended query protocol (Tatsuo Ishii)

      Unnecessary "flush" messages which used to be sent in each step of
      extended protocol messages (parse, bind, describe and execute) and
      brought significant communication overhead are removed. For now it
      only affects to streaming replication mode, that is, the performance
      of other modes remains same.

    - watchdog feature enhancements (Muhammad Usama, Yugo Nagata)

      The goal of this enhancement is to address the shortcomings and problems
      in the pgpool watchdog and make the watchdog system more robust and
      adaptable. Patch created by Usama, and reviewed, tested, and debugged
      by Yugo.

        -- The watchdog should consider the quorum and only elect the master/leader
           node if the quorum exist in the watchdog cluster.
        -- All the participating pgpool-II nodes in the watchdog cluster should have
           similar pgpool-II configurations.
        -- Watchdog nodes should have configurable watchdog node priority, to give
           users more control on which node should become a leader node.
        -- More options for the node health-checking, especially watchdog should allow
           external/3rd party node health checking system to integrate with it.
        -- The watchdog should keep looking for problems like split-brain syndrome and
           should automatically recover from it.
        -- Allow user to provide scripts to be executed at time of escalation and
           de-escalation to master/leader nodes.

      Add these new parameters:

        -- wd_ipc_socket_dir:
           This parameter is used to specify the directory where the UNIX domain
           socket accepting pgpool-II watchdog IPC connections will be created.

        -- wd_priority:
           This new parameter can be used to elevate the current watchdog node
           priority in leader elections. The node with the higher wd_priority
           value will get selected as master/coordinator watchdog node when
           cluster will be electing its master node at cluster startup or in the
           event of old master watchdog node failure.

        -- wd_de_escalation_command:
           This parameter holds the command that watchdog will execute on the
           master pgpool-II watchdog node when that node resigns from the master
           node responsibilities.

        -- wd_monitoring_interfaces_list:
           This parameter holds a comma separated list of network device names to
           be monitored by the watchdog process for the network link state.

    - Overhauling pcp commands (Muhammad Usama)

        -- Improved handling of command argument:
           Long command line options can be used now.
        -- PCP password is safe:
           Don't pass password via command line, which causes security risks.
        -- Multiple concurrent execution of pcp commands:
           Allow to execute a pcp command while running pcp_recovery_node
           which takes sometime to finish.

    - SELECT count statics in "show pool_nodes" command results (Tatsuo Ishii)

      show pool_nodes results which briefly describes the status of each backend
      now shows how many SELECTs are issued to them. So you can quickly
      recognize the effect of load balancing for example;

        test=# show pool_nodes;
         node_id | hostname | port  | status | lb_weight |  role   | select_cnt
        ---------+----------+-------+--------+-----------+---------+------------
         0       | /tmp     | 11002 | 2      | 0.500000  | primary | 338230
         1       | /tmp     | 11003 | 2      | 0.500000  | standby | 163939
        (2 rows)

    - Parser enhancements for query rewriting (Yugo Nagata)

      INSERT/UPDATE/DELETE with WITH clause, writable CTE, RETURNING clause
      can now be properly handled in query rewriting in native replication mode.

    - Allow to open pool_passwd file in read only mode by pgpool-II main
      process (Tatsuo Ishii)

    - Allow to run pgpool in debug mode in regression tests (Tatsuo Ishii)

    - doc:Add pgpool_adm documents (Tatsuo Ishii)

    - doc:Update Chinese documents (Bambo Huang)

      __________________________________________________________________

* Bug fixes (since 3.4.3)

    - doc: Fix misinformation regarding load balancing in docs (Tatsuo Ishii)

      In streaming replication mode, DECLARE, FETCH, CLOSE and SHOW are sent
      to primary node only. Pointed out in [pgpool-general-jp: 1378].

    - Issue fsync() when writing pgpool_status. (Tatsuo Ishii)

      This ensures that pgpool_status is saved to permanent storage and
      allow to survive after system crash.

    - Fix reset query stuck problem (Muhammad Usama)

      It is reported that reset query (DISCARD ALL etc.) occasionally does
      not finish and pgpool child remain waiting for reply from the backend
      thus client cannot connect to pgpool (for example bug report #107).
      The cause of problem is not identified yet but if client suddenly
      closes connection to pgpool in the middle of query processing, backend
      may not accept the reset queries because they are not ready for query.

      The fix is to keep track of the status of frontend socket state and not
      caching the PostgreSQL connection if the connection to frontend was not
      properly terminated.

    - test: Fix false alarm of regression tset 062 (Yugo Nagata)

    - test: Fix broken regression test for native replication (Yugo Nagata)

      Test for insert-lock didn't work.

    - test: Fix regress test to sleep after pgpool_reload (Yugo Nagata)

      Some regression tests modify configuration file and reloads. However,
      sometimes these were not applied to pgpool just after reloading.

    - Fix inconsistency of sequence values in replication mode (Yugo Nagata)

      When a schema name was provided, the table name was quoted wrongly as
      like "public.mytbl" instead of "public"."mytbl". So, pool_regclass
      and to_regclass couldn't find right table oid and insert lock was
      never executed. This caused inconsistency between DB nodes.

    - test: Fix complication error and segfault of timestamp rewrite test (Yugo Nagata)

    - doc: Fix untranslated sentence in Japanese document (Yugo Nagata)

    - Fix ancient bug of pool_push() and friends. (Tatsuo Ishii)

      It allocates buffer using realloc and uses the pointer
      returned. However it does the pointer calculation *before* realloc
      gets called. So the calculation uses the old pointer value, which
      causes various problems including segfault later.

      Also there were other problems with it. The buffer pointer and buffer
      size variable is not initialized. The buffer is not freed by
      pool_close. Typo in debugging message (3.4 or later only). They are
      fixed as well.

    - doc: Fix wrong description in documents about log_standby_delay (Yugo Nagata)

    - Fix segfault that occurs when function is used in FROM clause (Yugo Nagata)

      PREPARE statements in streaming-reapplication mode and INSERT/UPDATE
      with SELECT in native-replication mode were affected. For example:

      - prepare p as select * from generate_series(1,1);
      - insert into tbl select now(), * from generate_series(1,1);

    - doc: Add caution about JDBC driver version regarding app_name_redirect_preference_list
      (Tatsuo Ishii)

    - Fix hang problem reported in bug #145. (Tatsuo Ishii)

      The problem occurs when all the condition below are met:

      1) pgpool-II 3.4 or later
      2) streaming replication mode
      3) primary node is also load balance node
      4) extended protocol is used
      5) client_idle_limit reached

    - Fix a in-memory query cache bug (Tatsuo Ishii)

      If extended query protocol is used and a bind/execute message arrives
      which uses a statement created by prior parse message, the temp_cache
      is not initialized by a parse messages. Thus messages are added to pre
      existing temp cache buffer which causes the trouble, that is, when the
      cached result returns, Data Row message and Command Complete message
      appeared twice.

      Per by bug #152.

    - test: Fix regression test 065. (Tatsuo Ishii)

      The path to JDBC driver was explicitly defined. This is wrong. This
      should be inherited from JDBC_DRIVER environment variable.

    - test: Fix possible hang-up of regression test 054.postgres_fdw (Yugo Nagata)

    - test: Add option to regress.sh and pgpool_setup for unix domain socket
      directory (Yugo Nagata)

    - doc: Add missing descriptions about default values to documents
      (Yugo Nagata)

    - test: Fix regression test 055 for rhel7 rpm (Yugo Nagata)

    - Fix reset query stuck problem (Muhammad Usama)

      The issue is already fixed in older branches and this fix adopts the
      same solution used by 3.3 series, i.e. closing the backend connection
      when client idle limit is reached.

    - Fix bug with "SET TRANSACTION READ ONLY" (Tatsuo Ishii)

      Pgpool-II remembers that non read only queries (including SET) were
      executed in an explicit transaction and adds a "writing transaction"
      mark to the transaction. The mark affects the query routing behavior
      of pgpool-II while running in streaming replication mode. Pgpool-II
      starts sending queries to the primary after the mark is set. Because
      the effect of writing queries may appear on standbys after some delay
      in streaming replication mode, it is safer to route read queries to
      the primary after the mark is set.

      However there's oversight here. "SET TRANSACTION READ ONLY" does no
      data modification and should be treated as an exception.

      Per bug #157.

    - test: Fix to use timeout command to handle time out of regress test 062
      (Yugo Nagata)

    - Fix to show wrong error (Tatsuo Ishii)

      connect_with_timeout() does not show proper error info when
      getsockopt(SO_ERROR) reports an error. Pointed out in bug #159.

    - test: Add regress.sh missing \n in help messages (Yugo Nagata)

    - Fix the logic issue in get_backends_status() function (Muhammad Usama)

      get_backends_status () function counts the number of current valid and down
      backend nodes. The function assumed that the node was also invalid when its
      connection status was down. However, that is not always right.

    - Fix white/black_memqcache_table_list  not to require quotation (Yugo Nagata)

      The tables and schemas name specified in *_memqcache_table_list
      were needed to be quoted by double quotation.

      Patch contributed by Dang Minh Huong.
      Per [pgpool-hackers: 1323]

    - Fix FATAL error with reloading (Tatsuo Ishii)

      While reloading pgpool.conf, the number of DB nodes is tentatively set
      to 0, then counted up until reaching to the actual number of backends
      by the pgpool main process. Unfortunately the variable was on the
      shared memory and it confused pgpool child process when they were using
      the variable and this caused FATAL error.

      Per bug #156 report by harukat.

    - test: Add some tests for white/black_memqcache_table_list to regression
      test 006.memqcache (Yugo Nagata)

    - Fix reset query stuck problem (Muhammad Usama, Tatsuo Ishii)

      When pool_read fails to read from frontend or pool_flush fails to
      write to the frontend, report FRONTEND_ERROR, rather than ERROR to
      disconnect and terminate pgpool child process, to prevent the query
      stuck problem.

    - test: Fix some regression tests that failed in debug mode (Yugo Nagata)

    - Fix performance degradation while using IPv6 (Muhammad Usama)

      Per bug #165.

===============================================================================
3.4 Series (2014/11/07 - )
===============================================================================

                        3.4.8 (tataraboshi) 2016/08/31

* Version 3.4.8

    This is a bugfix release against pgpool-II 3.4.7.

    __________________________________________________________________

* Bug fixes

    - Fix buffer over run problem in "show pool_nodes". (Tatsuo Ishii)

      While processing "show pool_nodes", the buffer for hostname was too
      short. It should be same size as the buffer used for pgpool.conf.
      Problem reported by a twitter user who is using pgpool on AWS (which
      could have very long hostname).

    - Fix usage of wait(2) in pgpool main process. (Tatsuo Ishii)

      The usage of wait(2) in pgpool main could cause infinite wait in the
      system call. Solution is, to use waitpid(2) instead of wait(2).

    - Save and restore errno in each signal handler. (Tatsuo Ishii)

    - Fix handling of pcp_listen_addresses config parameter. (Muhammad Usama)

    - Fix "kind mismatch" error message in pgpool. (Muhammad Usama)

      Many of "kind mismatch..." errors are caused by notice/warning
      messages produced by one or more of the DB nodes. In this case now
      Pgpool-II forwards the messages to frontend, rather than throwing the
      "kind mismatch..." error. This would reduce the chance of "kind
      mismatch..."  errors.

      See [pgpool-hackers: 1501] for more details.

    - Replace "MAJOR" macro to prevent occasional failure. (Tatsuo Ishii)

      The macro calls pool_virtual_master_db_node_id() and then access
      backend->slots[id]->con using the node id returned.  In rare cases, it
      could point to 0 (in case when the DB node is not connected), which
      gives access to con->major, then it causes a segfault.

      See bug 225 for related info.

    - doc : Fixing a typo in english doc (Muhammad Usama)

    - doc : fix Japanese document typo. (Bo Peng)

    - Fixing a typo in the log message. (Muhammad Usama)

    - Tighten up health check timer expired condition in pool_check_fd(). (Muhammad Usama)

    - doc : Add comment to the document about connection_cache. (Tatsuo Ishii)

    - Fix for 237 that Pgpool-II fails to start if listen_addresses is empty string.
      (Muhammad Usama)

      The socket descriptor array (fds[]) was not getting the array end marker
      when TCP listen addresses are not used.

      See bug 237 for related info.

===============================================================================

                        3.4.7 (tataraboshi) 2016/06/17

* Version 3.4.7

    This is a bugfix release against pgpool-II 3.4.6.

    __________________________________________________________________

* New features

    - Allow to access to pgpool while doing health checking (Tatsuo Ishii)

      Currently any attempt to connect to pgpool fails if pgpool is doing
      health check against failed node even if fail_over_on_backend_error is
      off because pgpool child first tries to connect to all backend
      including the failed one and exits if it fails to connect to a backend
      (of course it fails). This is a temporary situation and will be
      resolved before pgpool executes failover. However if the health check
      is retrying, the temporary situation keeps longer depending on the
      setting of health_check_max_retries and health_check_retry_delay. This
      is not good. Attached patch tries to mitigate the problem:

      - When an attempt to connect to backend fails, give up connecting to
      the failed node and skip to other node, rather than exiting the
      process if operating in streaming replication mode and the node is
      not primary node.

      - Mark the local status of the failed node to "down".

      - This will let the primary node be selected as a load balance node
      and every queries will be sent to the primary node. If there's other
      healthy standby nodes, one of them will be chosen as the load
      balance node.

      - After the session is over, the child process will suicide to not
      retain the local status.

      Per [pgpool-hackers: 1531].

* Bug fixes

    - Fix is_set_transaction_serializable() when
      SET default_transaction_isolation TO 'serializable'. (Bo Peng)

      SET default_transaction_isolation TO 'serializable' is sent to
      not only primary but also to standby server in streaming replication mode,
      and this causes an error. Fix is, in streaming replication mode,
      SET default_transaction_isolation TO 'serializable' is sent only to the
      primary server.

      See bug 191 for related info.

    - Fix Chinese documentation bug about raw mode (Yugo Nagata, Bo Peng)
      Connection pool is available in raw mode.

    - Fix confusing comments in pgpool.conf (Tatsuo Ishii)

    - Permit pgpool to support multiple SSL cipher protocols (Muhammad Usama)

      Currently TLSv1_method() is used to initialize the SSL context, that puts an
      unnecessary limitation to allow only TLSv1 protocol for SSL communication.
      While postgreSQL supports other ciphers protocols as well. The commit changes
      the above and initializes the SSLSession using the SSLv23_method()
      (same is also used by PostgreSQL). Because it can negotiate the use of the
      highest mutually supported protocol version and remove the limitation of one
      specific protocol version.

    - If statement timeout is enabled on backend and do_query() sends a (Tatsuo Ishii)
      query to primary node, and all of following user queries are sent to
      standby, it is possible that the next command, for example END, could
      cause a statement timeout error on the primary, and a kind mismatch
      error on pgpool-II is raised.

      This fix tries to mitigate the problem by sending sync message instead
      of flush message in do_query(), expecting that the sync message reset
      the statement timeout timer if we are in an explicit transaction. We
      cannot use this technique for implicit transaction case, because the
      sync message removes the unnamed portal if there's any.

      Plus, pg_stat_statement will no longer show the query issued by
      do_query() as "running".

      See bug 194 for related info.

    - Fix a possible hang during health checking (Yugo Nagata)

      Health checking was hang when any data wasn't sent
      from backend after connect(2) succeeded. To fix this,
      pool_check_fd() returns 1 when select(2) exits with
      EINTR due to SIGALRM while health checking is performed.

      Reported and patch provided by harukat and some modification
      by Yugo.

      See bug 204 for related info.

    - change the Makefile under this directory src/sql/,that is proposed by (Bo Peng)
      [pgpool-hackers: 1611]

    - Fix bug with load balance node id info on shmem (Tatsuo Ishii)

      There are few places where the load balance node was mistakenly put on
      wrong place. It should be placed on:
      ConnectionInfo *con_info[child id, connection pool_id, backend id].load_balancing_node].
      In fact it was placed on:
      *con_info[child id, connection pool_id, 0].load_balancing_node].

      As long as the backend id in question is 0, it is ok. However while
      testing pgpool-II 3.6's enhancement regarding failover, if primary
      node is 1 (which is the load balance node) and standby is 0, a client
      connecting to node 1 is disconnected when failover happens on node
      0. This is unexpected and the bug was revealed.

      It seems the bug was there since long time ago but it had not found
      until today by the reason above.


    - Deal with the case when the primary is not node 0 in streaming replication mode. (Tatsuo Ishii)

      http://www.pgpool.net/mantisbt/view.php?id=194#c837 reported that if
      primary is not node 0, then statement timeout could occur even after
      bug194-3.3.diff was applied. After some investigation, it appeared
      that MASTER macro could return other than primary or load balance
      node, which was not supposed to happen, thus do_query() sends queries
      to wrong node (this is not clear from the report but I confirmed it in
      my investigation).

      pool_virtual_master_db_node_id(), which is called in MASTER macro
      returns query_context->virtual_master_node_id if query context
      exists. This could return wrong node if the variable has not been set
      yet. To fix this, the function is modified: if the variable is not
      either load balance node or primary node, the primary node id is
      returned.

===============================================================================

                        3.4.6 (tataraboshi) 2016/04/26

* Version 3.4.6

    This is a bugfix release against pgpool-II 3.4.5.

    __________________________________________________________________

* Bug fixes

    - Fix for segfault during trusted_servers check (Muhammad Usama)

      PostgreSQL's memory and exception manager APIs adopted by the
      pgpool 3.4 are not thread safe and are causing the segmentation fault
      in the watchdog lifecheck process, as it uses the threads to ping
      configured trusted hosts for checking the upstream connections.
      Fix is to remove threads and use the child process approach instead.

      See [pgpool-general: 4569] for more details.

    - Removing the limit on the maximum number of items in the
      black_function_list and white_function_list lists. (Muhammad Usama)

      extract_string_tokens in pool_config uses the fixed size malloc on
      the array to hold the black_function_list/white_function_list items.
      This imposes a limit of maximum items in these lists.
      The fix is to use realloc to increase the array size when it gets full.

    - Redirect all user queries to primary server (Tatsuo Ishii)

      Up to now some user queries are sent to other than the primary server
      even if load_balance_mode = off. This commit changes the behavior: if
      load_balance_mode = off in streaming replication mode, now all the
      user queries are sent to the primary server only.

      Per bug #189.

    - Change the PID length of pcp_proc_count command result to 6 characters
      long (Bo Peng)

      If the pgpool process ID are over 5 characters, the 6th character of each
      process ID will be removed. This commit changes the process ID length of
      pcp_proc_count command result to 6 characters long.

      Per bug #188.

===============================================================================

                        3.4.5 (tataraboshi) 2016/04/04

* Version 3.4.5

    This is a bugfix release against pgpool-II 3.4.4.

    __________________________________________________________________

* Bug fixes

    - test: Fix test/regression/clean.sh to remove binary files of
      010.rewrite_timestamp test (Yugo Nagata)

    - Fix memory leak reported by Coverity (CID 1350095) (Yugo Nagata)

    - Fixing pgpool-recovery module compilation issue with PostgreSQL 9.6
      (Muhammad Usama)

      Incorporating the change of function signature for GetConfigOption..()
      functions in PostgreSQL 9.6.

    - Fix a reset query stuck problem (Muhammad Usama)

      The solution is to report FRONTEND_ERROR instead of simple ERROR when
      pool_flush on front-end socket fails.

      The original report is
      [pgpool-general: 4265] Pgpool - connection hangs in DISCARD ALL

      The patch was generated by Usama and Pawel Ufnalewski<archon@foap.com>,
      and Gerhard Wiesinger <lists@wiesinger.com> helped to verify and test
      the fix.

    - Fix typo in configure (Tatsuo Ishii)

      Patch provided by Thomas Munro.

    - doc: Change description of backend_flag (Tatsuo Ishii)

      It is pointed out that restarting pgpool-II is not necessary.

      Per [pgpool-general-jp: 1394].

    - doc: Fix installation procedure. (Tatsuo Ishii)

      With PostgreSQL 9.4 or later, installing pgpool_regclass is not needed.

    - test: Fix pgpool_setup to not confuse log output (Tatsuo Ishii)

      Before it simply redirects stdout and stderr of pgpool processes to
      a log file. This could cause the log contents being garbled or even
      missed because of race condition caused by multiple process being
      writing concurrently.

      To fix this, pgpool_setup now generates startall script in which pgpool
      sends stdout/stderr to cat command by pipe, and cat writes to the log
      file.

    - Fix to validate the PCP packet length (Muhammad Usama)

      Without the validation check, a malformed PCP packet can crash the
      PCP child and/or can run the server out of memory by sending the packet
      with a very large data size.

===============================================================================

                        3.4.4 (tataraboshi) 2016/02/05

* Version 3.4.4

    This is a bugfix release against pgpool-II 3.4.3.

    __________________________________________________________________

* Bug fixes

    - doc: Fix misinformation regarding load balancing in docs (Tatsuo Ishii)

      In streaming replication mode, DECLARE, FETCH, CLOSE and SHOW are sent
      to primary node only. Pointed out in [pgpool-general-jp: 1378].

    - Issue fsync() when writing pgpool_status (Tatsuo Ishii)

      This ensures that pgpool_status is saved to permanent storage and
      allow to survive after system crash.

    - Fix reset query stuck problem (Muhammad Usama)

      It is reported that reset query (DISCARD ALL etc.) occasionally does
      not finish and pgpool child remain waiting for reply from the backend
      thus client cannot connect to pgpool (for example bug report #107).
      The cause of problem is not identified yet but if client suddenly
      closes connection to pgpool in the middle of query processing, backend
      may not accept the reset queries because they are not ready for query.

      The fix is to keep track of the status of frontend socket state and not
      caching the PostgreSQL connection if the connection to frontend was not
      properly terminated.

    - test: Fix false alarm of regression tset 062 (Yugo Nagata)

    - test: Fix broken regression test for native replication (Yugo Nagata)

      Test for insert lock didn't work.

    - test: Fix regress test to sleep after pgpool_reload (Yugo Nagata)

      Some regression tests modify configuration file and reloads. However,
      sometimes these were not applied to pgpool just after reloading.

    - Fix inconsistency of sequence values in replication mode (Yugo Nagata)

      When a schema name was provided, the table name was quoted wrongly as
      like "public.mytbl" instead of "public"."mytbl". So, pool_regclass
      and to_regclass couldn't find right table oid and insert lock was
      never executed. This caused inconsistency between DB nodes.

    - test: Fix complication error and segfault of timestamp rewrite test
      (Yugo Nagata)

    - test: Add timestamp-rewrite unit test to regression test suite (Yugo Nagata)

    - doc: Fix untranslated sentence in Japanese document (Yugo Nagata)

    - Fix ancient bug of pool_push() and friends (Tatsuo Ishii)

      It allocates buffer using realloc and uses the pointer
      returned. However it does the pointer calculation *before* realloc
      gets called. So the calculation uses the old pointer value, which
      causes various problems including segfault later.

      Also there were other problems with it. The buffer pointer and buffer
      size variable is not initialized. The buffer is not freed by
      pool_close. Typo in debugging message (3.4 or later only). They are
      fixed as well.

    - doc: Fix wrong description about log_standby_delay in the document
      (Yugo Nagata)

    - doc: Add caution about JDBC driver version regarding
      app_name_redirect_preference_list (Tatsuo Ishii)

    - Fix hang problem reported in bug#145 (Tatsuo Ishii)

      The problem occurs when all the condition below are met:

      1) pgpool-II 3.4 or later
      2) streaming replication mode
      3) primary node is also load balance node
      4) extended protocol is used
      5) client_idle_limit reached

    - test: Fix regression test 065 (Tatsuo Ishii)

      The path to JDBC driver was explicitly defined. This is wrong. This
      should be inherited from JDBC_DRIVER environment variable.

    - test: Fix possible hang-up of regression test 054.postgres_fdw (Yugo Nagata)

    - test: Add option to regress.sh and pgpool_setup for unix domain socket
      directory (Yugo Nagata)

    - doc: Add missing descriptions about default values to documents (Yugo Nagata)

    - test: Fix a bug of regress.sh option handling (Yugo Nagata)

    - test: Fix regression test 055.backend_all_down to use PGSOCKET_DIR for
      PostgreSQL rhel7 rpm (Yugo Nagata)

    - Fix reset query stuck problem (Muhammad Usama)

      The issue is already fixed in older branches and this fix adopts the
      same solution used by 3.3 series, i.e. closing the backend connection
      when client idle limit is reached.

    - Fix bug with "SET TRANSACTION READ ONLY" (Tatsuo Ishii)

      Pgpool-II remembers that non read only queries (including SET) were
      executed in an explicit transaction and adds a "writing transaction"
      mark to the transaction. The mark affects the query routing behavior
      of pgpool-II while running in streaming replication mode. Pgpool-II
      starts sending queries to the primary after the mark is set. Because
      the effect of writing queries may appear on standbys after some delay
      in streaming replication mode, it is safer to route read queries to
      the primary after the mark is set.

      However there's oversight here. "SET TRANSACTION READ ONLY" does no
      data modification and should be treated as an exception.

      Per bug #157.

    - test: Fix to use timeout command to handle time out of regress test 062
      (Yugo Nagata)

    - Fix to show wrong error (Tatsuo Ishii)

      connect_with_timeout() does not show proper error info when
      getsockopt(SO_ERROR) reports an error. Pointed out in bug #159.

    - test: Add missing \n in help messages (Yugo Nagata)

    - Fixing the logic issue in get_backends_status() function (Muhammad Usama)

      get_backends_status () function counts the number of current valid and down
      backend nodes. The function assumed that the node was also invalid when its
      connection status was down. However, that is not always right.

    - test: Fix regression test 003.failover for rhel7 postgresql rpm (Yugo Nagata)

      The expected result of 'show pool_nodes' is fixed to use
      PGSOCKET_DIR in hostname column.

    - Fix white/black_memqcache_table_list not require quotation (Yugo Nagata)

      The tables and schemas name specified in *_memqcache_table_list
      were needed to be quoted by double quotation.

      Patch contributed by Dang Minh Huong.
      Per [pgpool-hackers: 1323]

    - Fix FATAL error with reloading (Tatsuo Ishii)

      While reloading pgpool.conf, the number of DB nodes is tentatively set
      to 0, then counted up until reaching to the actual number of backends
      by the pgpool main process. Unfortunately the variable was on the
      shared memory and it confused pgpool child process when they were using
      the variable and this caused FATAL error.

      Per bug #156 report by harukat.

    - test: Add some tests for white/black_memqcache_table_list to regression
      test 006.memqcache (Yugo Nagata)

    - Fix reset query stuck problem (Muhammad Usama, Tatsuo Ishii)

      When pool_read fails to read from frontend or pool_flush fails to
      write to the frontend, report FRONTEND_ERROR, rather than ERROR to
      disconnect and terminate pgpool child process, to prevent the query
      stuck problem.

    - test: Fix regression test 008 & 009 failure in debug mode (Yugo Nagata)

    - Fix performance degradation while using IPv6 (Muhammad Usama)

      Per bug #165.

    - Add some warning messages for wd_authkey hash calculation failure
      (Yugo Nagata)

      Sometimes wd_authkey calculation fails for some reason other than
      authkey mismatch. The additional messages make these distinguishable
      for each other.

    - test: Fix regression test to check timeout of each test (Yugo Nagata)

    - test: Allow timeout value to be specified by the command option (Yugo Nagata)

    - Fix bugs with data modifying WITH clause. (Tatsuo Ishii)

      pgpool-II did not recognize the data modifying WITH clause despite
      pgpool-II 3.3 or after has SQL parser which recognizes it. The bug has
      been fixed in pgpool-II 3.5 (having PostgreSQL 9.5 parser), and the fix
      is back ported to pgpool-II 3.3 and 3.4.

      Per bug #153.

    - Fix segfault that occurs when function is used in FROM clause (Yugo Nagata)

      PREPARE statements in streaming-reapplication mode and INSERT/UPDATE
      with SELECT in native-replication mode were affected. For example:

      - prepare p as select * from generate_series(1,1);
      - insert into tbl select now(), * from generate_series(1,1);

    - Fix broken arping_cmd configuration check(Muhammad Usama)

      wd_chk_setuid() function was bailing out with the NOTICE message as soon
      as it finds the setuid bit is not set on any configured network command
      and was ignoring the rest of configurations.

      Per bug #139.

    - doc: Add restriction about starting multiple pgpool simultaneously
      (Yugo Nagata)

    - Fix to use saved errno for erreport instead of the direct value
      (Yugo Nagata)

      Some system calls are called in errmsg() and errhint(), and
      it isn't safe to pass errno directly as an argument. This caused
      the confusable log message as below.

      DETAIL: connect() reports failure "Success"

    - Fix a in-memory query cache bug (Tatsuo Ishii)

      If extended query protocol is used and a bind/execute message arrives
      which uses a statement created by prior parse message, the temp_cache
      is not initialized by a parse messages. Thus messages are added to pre
      existing temp cache buffer which causes the trouble, that is, when the
      cached result returns, Data Row message and Command Complete message
      appeared twice.

      Per by bug #152.

    - Fix a compile issue on freebsd, added missing include files (Muhammad Usama)

===============================================================================

                        3.4.3 (tataraboshi) 2015/07/24

* Version 3.4.3

    This is a bugfix release against pgpool-II 3.4.2.

    __________________________________________________________________

* Bug fixes

    - Fix "cannot find xlog functions" error in pgpool-recovery
      (Muhammad Usama)

      The argument data type of PostgreSQL's pg_xlogfile_name() function
      has been changed from text to pg_lsn since PostgreSQL 9.4. And
      pgpool-recovery was still trying to locate the function by old
      signature.

    - Fix problem with memory cache invalidation (Muhammad Usama)

      The internal buffer for storing the table oids needs to be homed in
      long living memory context as it has to survive throughout the child
      life.

      See [pgpool-general: 3643] for details.

    - Pass empty string parameters in failover command when pgpool-II
      does not have a value for any particular parameter (Muhammad Usama)

      Instead of omitting the values for the parameters when pgpool-II does
      not have any value for a particular parameter, it now passes an empty
      string to the failover command. This makes sure that failover script
      will always receive the exact number of expected parameters.

    - pgpool-II should use the local definition of snprintf functions only
      if they are not provided by OS (Muhammad Usama)

    - Add debug info to show how much shared memory is allocated
      (Tatsuo Ishii)

    - Downgrading the error level for EOF on backend connection for main
      process (Muhammad Usama)

      Throwing the FATAL error when EOF is encountered with backend is very
      harsh in pgpool main process and can cause undesirable behavior.
      Downgrading it to simple ERROR.

    - doc: Clarify load balancing condition (Tatsuo Ishii)

    - doc: Clarify description of pcp_promote_node (Tatsuo Ishii)

      It does not actually promote PostgreSQL standby.

    - doc: Fix outdated limitation description about load balancing using
      JDBC driver (Tatsuo Ishii)

      Even if autocommit is false, load balancing is possible in certain
      conditions.

    - Fix a misplaced code which makes a log code unreachable and rephrase
      the log message (Muhammad Usama)

    - Fix a problem in elog.c when forwarding a message to frontend clients
      (Muhammad Usama)

      Error while forwarding the message to the frontend client can
      potentially cause the infinite recursion and terminate the child with
      ERRORDATA_STACK_SIZE exceeded error.

      Fix is to check the recursion depth of send_message_to_frontend()
      function and pulling the plug if it is more than two levels deep.

    - Fix "select() system call interrupted" error (Tatsuo Ishii)

      The health check process complains above and then:

      ERROR:  failed to make persistent db connection
      DETAIL:  connection to host:"x.x.x.x:5432 failed

      However, the healthcheck triggers neither fail over nor retrying. So,
      except the annoying messages above, everything goes well. This could
      occur more easily if 1) num_init_children is big and 2) pgpool
      children go into idle state (no query arrived from client for
      child_life_time seconds).

      Original bug report is [pgpool-general: 3756] Connection Interrupted.
      Patch created by Tatsuo Ishii. Enhancement from Usama.

    - Fix the case when user table includes spaces (Tatsuo Ishii)

      For example if table names including spaces are used, pgpool-II cannot
      be handled correctly by the internal functions which access system
      catalogs and it results in SQL errors. Solution is, to always use
      delimited identifier.

      Per bug #136.
      http://www.pgpool.net/mantisbt/view.php?id=136

      Also see [pgpool-general: 3818].

    - Allow to use in-memory query cache size more than 4GB (Tatsuo Ishii)

      This should have been allowed since in memory query cache was born.

    - Do not send a query for checking insert lock in non replication mode
      with extended query (Tatsuo Ishii)

    - Save pgpool_status to disk each time when it is changed
      (Tatsuo Ishii)

      Previously, pgpool-II saves pgpool_status file when pgpool-II
      explicitly is going shutdown. This is fine in most cases and it saves
      slight CPU cycles. But if pgpool-II killed abnormally or the system
      forces pgpool-II to go down by OOM killer, next pgpool-II restarting
      could load obsolete status file.

===============================================================================

                        3.4.3 (tataraboshi) 2015/07/24

* Version 3.4.3

    This is a bugfix release against pgpool-II 3.4.2.

    __________________________________________________________________

* Bug fixes

    - Fix "cannot find xlog functions" error in pgpool-recovery
      (Muhammad Usama)

      The argument data type of PostgreSQL's pg_xlogfile_name() function
      has been changed from text to pg_lsn since PostgreSQL 9.4. And
      pgpool-recovery was still trying to locate the function by old
      signature.

    - Fix problem with memory cache invalidation (Muhammad Usama)

      The internal buffer for storing the table oids needs to be homed in
      long living memory context as it has to survive throughout the child
      life.

      See [pgpool-general: 3643] for details.

    - Pass empty string parameters in failover command when pgpool-II
      does not have a value for any particular parameter (Muhammad Usama)

      Instead of omitting the values for the parameters when pgpool-II does
      not have any value for a particular parameter, it now passes an empty
      string to the failover command. This makes sure that failover script
      will always receive the exact number of expected parameters.

    - pgpool-II should use the local definition of snprintf functions only
      if they are not provided by OS (Muhammad Usama)

    - Add debug info to show how much shared memory is allocated
      (Tatsuo Ishii)

    - Downgrading the error level for EOF on backend connection for main
      process (Muhammad Usama)

      Throwing the FATAL error when EOF is encountered with backend is very
      harsh in pgpool main process and can cause undesirable behavior.
      Downgrading it to simple ERROR.

    - doc: Clarify load balancing condition (Tatsuo Ishii)

    - doc: Clarify description of pcp_promote_node (Tatsuo Ishii)

      It does not actually promote PostgreSQL standby.

    - doc: Fix outdated limitation description about load balancing using
      JDBC driver (Tatsuo Ishii)

      Even if autocommit is false, load balancing is possible in certain
      conditions.

    - Fix a misplaced code which makes a log code unreachable and rephrase
      the log message (Muhammad Usama)

    - Fix a problem in elog.c when forwarding a message to frontend clients
      (Muhammad Usama)

      Error while forwarding the message to the frontend client can
      potentially cause the infinite recursion and terminate the child with
      ERRORDATA_STACK_SIZE exceeded error.

      Fix is to check the recursion depth of send_message_to_frontend()
      function and pulling the plug if it is more than two levels deep.

    - Fix "select() system call interrupted" error (Tatsuo Ishii)

      The health check process complains above and then:

      ERROR:  failed to make persistent db connection
      DETAIL:  connection to host:"x.x.x.x:5432 failed

      However, the healthcheck triggers neither fail over nor retrying. So,
      except the annoying messages above, everything goes well. This could
      occur more easily if 1) num_init_children is big and 2) pgpool
      children go into idle state (no query arrived from client for
      child_life_time seconds).

      Original bug report is [pgpool-general: 3756] Connection Interrupted.
      Patch created by Tatsuo Ishii. Enhancement from Usama.

    - Fix the case when user table includes spaces (Tatsuo Ishii)

      For example if table names including spaces are used, pgpool-II cannot
      be handled correctly by the internal functions which access system
      catalogs and it results in SQL errors. Solution is, to always use
      delimited identifier.

      Per bug #136.
      http://www.pgpool.net/mantisbt/view.php?id=136

      Also see [pgpool-general: 3818].

    - Allow to use in-memory query cache size more than 4GB (Tatsuo Ishii)

      This should have been allowed since in memory query cache was born.

    - Do not send a query for checking insert lock in non replication mode
      with extended query (Tatsuo Ishii)

    - Save pgpool_status to disk each time when it is changed
      (Tatsuo Ishii)

      Previously, pgpool-II saves pgpool_status file when pgpool-II
      explicitly is going shutdown. This is fine in most cases and it saves
      slight CPU cycles. But if pgpool-II killed abnormally or the system
      forces pgpool-II to go down by OOM killer, next pgpool-II restarting
      could load obsolete status file.

===============================================================================

                        3.4.2 (tataraboshi) 2015/04/08

* Version 3.4.2

    This is a bugfix release against pgpool-II 3.4.1.

    __________________________________________________________________

* Bug fixes

    - rpm: Fix %tmpfiles_create to not be executed in RHEL/CentOS 6
      (Nozomi Anzai)

    - Fix to reset on_exit call back functions in exec_if_cmd and exec_ping
      worker processes (Muhammad Usama)

      exec_if and exec_ping child processes were inheriting the parent exit
      callback functions which could result in undesired behavior if one of
      these commands fails. Fixed by adding on_exit_reset() at child start-up
      in both processes.

    - Fix to use void * type for receiving return value of thread function
      (Yugo Nagata)

      Previously int type was used and this could occur stack buffer
      overflow. This caused an infinity loop of ping error at bringing
      up or down VIP.

    - Fix to set SIGCHLD to SIG_DFL instead of SIG_IGN in watchdog processes
      (Yugo Nagata)

      When using waitpid, it isn't necessary to set SIGCHLD to SIG_IGN.
      Rather, it is harmful, and due to this it was regarded that ping
      command exited abnormally in error even when this succeeded.

    - Fix to use waitpid instead of wait in exec_ifconfig (Yugo Nagata)

    - Remove an unnecessary include directive (Yugo Nagata)

    - Enlarge POOLCONFIG_MAXDESCLEN to 80 (Tatsuo Ishii)

      This is used in show pool_status command and limits the length of
      parameter description.  Unfortunately recovery_timeout description is
      64 chars, which is 1 byte longer than former definition of the macro.

    - doc: Update document of condition for load balancing (Yugo Nagata)

      Load balancing is possible in an explicit transaction block
      even in replication mode since 3.3.0.

    - Support SSL certificate chains in the certificate file for incoming
      frontend connections (Muhammad Usama)

    - Use to_regclass if available in time stamp rewriting in replication
      mode (Tatsuo Ishii)

    - Fix to not emits a fatal error message when clear text password auth
      is used (Muhammad Usama)

      The problem was introduced in pgpool-II after inclusion of exception
      manager. EOF on the frontend connection during client authentication
      should not be treated as an error when the password authentication
      method is used. psql disconnects from the server in such case to get
      the password from the terminal, reconnects and sends the read password
      to server.

    - previous session for the same child had exited because of some ERROR.
      (Muhammad Usama)

    - Fix a hang when an error occurs in a transaction block with
      replication mode (Yugo Nagata)

      When an error occurs at a backend node in a transaction block with
      replication mode, pgpool-II sends an invalid query to other
      backends to sync transaction states. However, previously, this was
      not sent to master node, and pgpool-II was waiting for master's
      response forever.

    - Fix a problem with pcp_detach_node about graceful node detach (Muhammad Usama)

      When graceful node detach is requested gracefully, pcp_detach_node should
      check if it is allowed to process detach_node command on the particular
      node before blocking the incoming connections and closing the existing
      connections.

    - doc: Update table and flowchart of where a query should be sent to
      (Yugo Nagata)

    - rpm: pgpool.spec is required only in RHEL/CentOS 7 (Nozomi Anzai)

    - Fix a compilation issue about sighandler_t type on BSD variants
      (Muhammad Usama)

===============================================================================
                        3.4.1 (tataraboshi) 2015/02/05

* Version 3.4.1

    This is a bugfix release against pgpool-II 3.4.0.

    __________________________________________________________________

* Bug fixes

    - RPM: Add to support for memcached. (Tatsuo Ishii)

    - Fix number of parameters of pgpool_recovery from 3 to 4. (Tatsuo Ishii)

      This really should be done before releasing 3.4.0.

    - test: Allow pgpool_setup to set configuration file directory by setting
      environment variable PGPOOLDIR (Tatsuo Ishii)

    - RPM: Rename RPM file (Yugo Nagata)

      Rename filename to include the RHEL version number like PostgreSQL's
      official RPM file. (e.g. pgpool-II-pg93-3.4.0-2pgdg.rhel6.x86_64.rpm)

    - Fix node id range check bug in trigger_failover_command(). (Tatsuo Ishii)

      The node id should be lower than NUM_BACKENDS. Probably harmless since
      callers never pass node ids greater or equal to NUM_BACKENDS.

    - Fix occasional stuck that occurs when a NOTIFY message is sent from
      a backend. (Muhammad Usama)

      The issue happens in master slave mode with load balancing when the
      client is doing extended query messaging.

      per bug #116
      http://www.pgpool.net/mantisbt/view.php?id=116

    - test: Fix failover script of pgpool_setup to use absolute path to the
      database cluster (Tatsuo Ishii)

    - test: Reorganize port numbers assigned in pgpool_setup (Tatsuo Ishii)

      Assign base port (11000 by default) to pgpool, base port + 1 to pcp,
      port + 2 to PostgreSQL node0, port + 3 to PostgreSQL node1 and so on.

    - Fix a bug that pgpool-II 3.4 can't cancel query (Muhammad Usama)

    - test: Add regression test for cancelling query (Muhammad Usama)

    - Fix to not use non-thread-safe APIs in thread functions
      (Muhammad Usama)

      pgpool-II has borrowed the Memory and Exception managers from PostgreSQL
      which never utilizes the threads so its APIs are not thread safe.
      Previously, those API functions which manipulate the global variables
      in thread functions, and it caused to undefined behavior or a
      segmentation fault. Especially, the main process could die silently.

    - test: Add memory leak regression test (Tatsuo Ishii)

    - Fix a memory leak with long-lived connections (Muhammad Usama)

      Problem reported in [pgpool-general: 3325].

    - Change the log level of "Frontend Terminated" message to DEBUG1 from LOG
      (Muhammad Usama)

    - Fix ill signal behavior of SIGCHLD in exec_ifconfig() (Tatsuo Ishii)

      For some reason SIGCHLD was set to SIG_IGN *and* tries to wait
      child process which always fails because SIGCHLD is never delivered.
      Due to this "ifconfig up" fails when switching to watchdog master.

      See "[pgpool-general: 3310] for more details.

    - Allow $_IP_$ having address prefix in if_up_cmd and if_down_cmd
      (Muhammad Usama)

      Previously, it is assumed that "$_IP_$" keyword will always have a
      white space at the end, and when "$_IP_$" has address prefix (e.g.
      $_IP_$/24), this prefix was ignored.

      Per bug #122.
      http://www.pgpool.net/mantisbt/view.php?id=122

    - Fix to not send signal to init process (Muhammad Usama)

      This is more of a guard against a situation where a crash of the
      pgpool main process can make the child processes to send the signal
      to system's init process.

      Per bug #119.
      http://www.pgpool.net/mantisbt/view.php?id=119

    - RPM: Fix "error: Installed (but unpackaged) file(s) found" while
      creating RPMs for PostgreSQL 9.4 (Tatsuo Ishii)

    - Allow "show pool_nodes" to print node ids having more than one digits
      (Muhammad Usama)

      Problem reported in [pgpool-general: 3374].

    - Prevent "WARNING: failed to execute regex matching, pattern is NULL"
      message that could happen when application name is not set in the old
      clients (Tatsuo Ishii)

    - Fix pgpool main process to shutdown in case of child process start-up
      failures (Muhammad Usama)

      Problem reported in [pgpool-general: 3358].

    - Fix a segmentation fault that could happen in child process error
      (Muhammad Usama)

      Problem reported in [pgpool-general: 3377].

    - Fix occasional failure in regression test '004.watchdog' (Yugo Nagata)

      The patch provided by uehara in bug #127.
      http://www.pgpool.net/mantisbt/view.php?id=127

    - Fix client connection leak (Tatsuo Ishii)

      Since 3.4.0 pgpool-II child does not close the connection to client
      when it ends the session.  This leads to serious "CLOSE_WAIT" flood,
      which makes pgpool-II unusable since no new connection from clients
      accepted.

      Problem reported by Pablo Sanchez in [pgpool-general: 3394].

    - Restore SIGCHLD handler to its original after executing if_up/down_cmd
      (Yugo Nagata)

      Previously SIGCHLD was set to SIGIGN always after if_up/down_cmd.
      This led to a incorrect error handling of ping or other commands
      execution, and warning messages were output to log even when the
      command exited successfully.

    - RPM: Add pgpool.service for systemd in RHEL/CentOS 7 (Nozomi Anzai)

    - Fix process termination after several reload with enabled_pool_hba
      (Muhammad Usama)

    - Tighten up checking for app_name_redirect_preference_list and
      database_redirect_preference_list (Tatsuo Ishii)

      Before empty application name or database name or invalid DB node
      number were silently accepted. Now they are strictly checked and
      let raise fatal error when starting up.

      Problem reported in [pgpool-general-jp: 1337].

    - RPM: Change to use systemd if it is available (Nozomi Anzai)

    - Fix the behavior of "client_min_messages" configuration parameter
      (Muhammad Usama)

      This parameter controls the minimum message levels to be sent to the
      frontend. Previously, regardless of the value of the parameter all
      the messages with severity less than NOTICE level were not being
      forwarded to the client.

===============================================================================

                        3.4.0 (tataraboshi) 2014/11/07

* Version 3.4.0

      This is the first version of pgpool-II 3.4 series.
      That is, a "major version up" from 3.3 series.

      __________________________________________________________________

* Incompatible changes

    - Parallel query mode is obsoleted and is removed from
      pgpool.conf. This is due to the very few users using the mode
      (and the relatively high cost to maintain it).  Actual codes for
      the mode are still there and users can use the mode if they
      specify necessary parameters in pgpool.conf. Note, however, the
      next version of pgpool-II (will be 3.5.0) will actually remove
      the code.

    - "print_timestamp" parameter is removed. Instead new
      "log_line_prefix" should be used.

    - Recovery script now accepts 4 parameters, rather than 3 (the 4th
      parameter is the port number of master PostgreSQL). Existing
      3-parameter-style recovery scripts can be used if you don't care
      about information provided by the 4th parameter.
      __________________________________________________________________

* New features

    - Allow fine control of load balancing by using application name
      or database name. For example, if a client has particular
      application name, read queries can be redirect to master node,
      rather than to one of slave nodes (Tatsuo Ishii)

    - Allow to print pgpool-II process names in the log output. New
      parameter "log_line_prefix", which is the printf-style string
      that is output at the beginning of each log line (Muhammad Usama)

    - Allow to control log verbosity like PostgreSQL. For this purpose
      new parameters "log_error_verbosity", "client_min_messages",
      "log_min_messages" are added (Muhammad Usama)

    - Allow to use SQL comments without disturbing load balancing if
      new parameter "allow_sql_comments" is on. If it's off, previous
      behavior is kept (Tatsuo Ishii)

    - Allow to skip unlogged tables checking by using new parameter
      "check_unlogged_table". This reduces the number of pgpool-II's
      internal catalog look up queries and enhances performance
      (Tatsuo Ishii)

    - Prevent listen backlog overflow by using new parameter
      "listen_backlog_multiplier" for very busy systems (Tatsuo Ishii)

    - Prevent connection timeout to backend by using new parameter
      "connect_timeout". This is useful in unstable networks
      (Tatsuo Ishii)
      __________________________________________________________________

* Enhancements

    - Builtin SQL parser is now compatible with PostgreSQL 9.4 (Muhammad Usama)

    - Import PostgreSQL's memory manager and exception manager (Muhammad Usama)

    - Reorganize source code tree (Muhammad Usama)

    - The status file "pgpool_status" is now a plain ASCII file. This
      allows to register down PostgreSQL nodes before pgpool-II
      starts for example (Tatsuo Ishii)

    - Allow to use IPv6 address for PostgreSQ (Michael Stapelberg)

    - Allow to use IPv6 bind address for pgpool-II (Michael Stapelberg)

    - Rename all occurrence of "on memory query cache" to "in memory
      query cache" because latter is more correct in English (Tatsuo Ishii)

    - Add 4th parameter "master node port number" to recovery script
      (Tatsuo Ishii)

    - Allow to handle more than 3 database nodes in pgpool_setup
      (Tatsuo Ishii)
      __________________________________________________________________

* Bug fixes (since 3.3.4)

    - Fix failover deadlock problem in watchdog (Muhammad Usama). See
      bug #105 and [pgpool-committers: 2195] for more details.

    - As per the PostgreSQL specification, calling close on non
      existing portals is not an error. So on the same footings this
      commit ignores all such packets and return the 'close complete'
      message to client with out going to backend (Muhammad Usama)

    - Fix many issues/bugs found by Coverity (Muhammad Usama, Tatsuo Ishii)

===============================================================================
3.3 Series (2013/07/30 - )
===============================================================================

                        3.3.12 (tokakiboshi) 2016/08/31

* Version 3.3.12

    This is a bugfix release against pgpool-II 3.3.11.

    __________________________________________________________________

* Bug fixes

    - Fix buffer over run problem in "show pool_nodes". (Tatsuo Ishii)

      While processing "show pool_nodes", the buffer for hostname was too
      short. It should be same size as the buffer used for pgpool.conf.
      Problem reported by a twitter user who is using pgpool on AWS (which
      could have very long hostname).

    - Fix usage of wait(2) in pgpool main process. (Tatsuo Ishii)

      The usage of wait(2) in pgpool main could cause infinite wait in the
      system call. Solution is, to use waitpid(2) instead of wait(2).

    - Fix "kind mismatch" error message in pgpool. (Muhammad Usama)

      Many of "kind mismatch..." errors are caused by notice/warning
      messages produced by one or more of the DB nodes. In this case now
      Pgpool-II forwards the messages to frontend, rather than throwing the
      "kind mismatch..." error. This would reduce the chance of "kind
      mismatch..."  errors.

      See [pgpool-hackers: 1501] for more details.

    - Replace "MAJOR" macro to prevent occasional failure. (Tatsuo Ishii)

      The macro calls pool_virtual_master_db_node_id() and then access
      backend->slots[id]->con using the node id returned.  In rare cases, it
      could point to 0 (in case when the DB node is not connected), which
      gives access to con->major, then it causes a segfault.

      See bug 225 for related info.

    - doc : Fixing a typo in english doc (Muhammad Usama)

    - doc : fix Japanese document typo. (Bo Peng)

    - Fixing a typo in the log message. (Muhammad Usama)

    - doc : Add comment to the document about connection_cache. (Tatsuo Ishii)

===============================================================================

                        3.3.11 (tokakiboshi) 2016/06/17

* Version 3.3.11

    This is a bugfix release against pgpool-II 3.3.10.

    __________________________________________________________________

* New features

    - Allow to access to pgpool while doing health checking (Tatsuo Ishii)

      Currently any attempt to connect to pgpool fails if pgpool is doing
      health check against failed node even if fail_over_on_backend_error is
      off because pgpool child first tries to connect to all backend
      including the failed one and exits if it fails to connect to a backend
      (of course it fails). This is a temporary situation and will be
      resolved before pgpool executes failover. However if the health check
      is retrying, the temporary situation keeps longer depending on the
      setting of health_check_max_retries and health_check_retry_delay. This
      is not good. Attached patch tries to mitigate the problem:

      - When an attempt to connect to backend fails, give up connecting to
      the failed node and skip to other node, rather than exiting the
      process if operating in streaming replication mode and the node is
      not primary node.

      - Mark the local status of the failed node to "down".

      - This will let the primary node be selected as a load balance node
      and every queries will be sent to the primary node. If there's other
      healthy standby nodes, one of them will be chosen as the load
      balance node.

      - After the session is over, the child process will suicide to not
      retain the local status.

      Per [pgpool-hackers: 1531].

* Bug fixes

    - Fix is_set_transaction_serializable() when
      SET default_transaction_isolation TO 'serializable'. (Bo Peng)

      SET default_transaction_isolation TO 'serializable' is sent to
      not only primary but also to standby server in streaming replication mode,
      and this causes an error. Fix is, in streaming replication mode,
      SET default_transaction_isolation TO 'serializable' is sent only to the
      primary server.

      See bug 191 for related info.

    - Fix Chinese documentation bug about raw mode (Yugo Nagata, Bo Peng)
      Connection pool is available in raw mode.

    - Fix confusing comments in pgpool.conf (Tatsuo Ishii)

    - Permit pgpool to support multiple SSL cipher protocols (Muhammad Usama)

      Currently TLSv1_method() is used to initialize the SSL context, that puts an
      unnecessary limitation to allow only TLSv1 protocol for SSL communication.
      While postgreSQL supports other ciphers protocols as well. The commit changes
      the above and initializes the SSLSession using the SSLv23_method()
      (same is also used by PostgreSQL). Because it can negotiate the use of the
      highest mutually supported protocol version and remove the limitation of one
      specific protocol version.

    - If statement timeout is enabled on backend and do_query() sends a (Tatsuo Ishii)
      query to primary node, and all of following user queries are sent to
      standby, it is possible that the next command, for example END, could
      cause a statement timeout error on the primary, and a kind mismatch
      error on pgpool-II is raised.

      This fix tries to mitigate the problem by sending sync message instead
      of flush message in do_query(), expecting that the sync message reset
      the statement timeout timer if we are in an explicit transaction. We
      cannot use this technique for implicit transaction case, because the
      sync message removes the unnamed portal if there's any.

      Plus, pg_stat_statement will no longer show the query issued by
      do_query() as "running".

      See bug 194 for related info.

    - Deal with the case when the primary is not node 0 in streaming replication mode. (Tatsuo Ishii)

      http://www.pgpool.net/mantisbt/view.php?id=194#c837 reported that if
      primary is not node 0, then statement timeout could occur even after
      bug194-3.3.diff was applied. After some investigation, it appeared
      that MASTER macro could return other than primary or load balance
      node, which was not supposed to happen, thus do_query() sends queries
      to wrong node (this is not clear from the report but I confirmed it in
      my investigation).

      pool_virtual_master_db_node_id(), which is called in MASTER macro
      returns query_context->virtual_master_node_id if query context
      exists. This could return wrong node if the variable has not been set
      yet. To fix this, the function is modified: if the variable is not
      either load balance node or primary node, the primary node id is
      returned.

    - change the Makefile under the directory src/sql/, that is proposed (Bo Peng)
      by [pgpool-hackers: 1611]

    - Fix a possible hang during health checking (Yugo Nagata)

      Health checking was hang when any data wasn't sent
      from backend after connect(2) succeeded. To fix this,
      pool_check_fd() returns 1 when select(2) exits with
      EINTR due to SIGALRM while health checking is performed.

      Reported and patch provided by harukat and some modification
      by Yugo. Per bug #204.

      backported from 3.4 or later;
      https://git.postgresql.org/gitweb/?p=pgpool2.git;a=commitdiff;h=ed9f2900f1b611f5cfd52e8f758c3616861e60c0

    - Fix bug with load balance node id info on shmem (Tatsuo Ishii)

      There are few places where the load balance node was mistakenly put on
      wrong place. It should be placed on: ConnectionInfo *con_info[child
      id, connection pool_id, backend id].load_balancing_node].  In fact it
      was placed on: *con_info[child id, connection pool_id,
      0].load_balancing_node].

      As long as the backend id in question is 0, it is ok. However while
      testing pgpool-II 3.6's enhancement regarding failover, if primary
      node is 1 (which is the load balance node) and standby is 0, a client
      connecting to node 1 is disconnected when failover happens on node
      0. This is unexpected and the bug was revealed.

      It seems the bug was there since long time ago but it had not found
      until today by the reason above.

===============================================================================

                        3.3.10 (tokakiboshi) 2016/04/26

* Version 3.3.10

    This is a bugfix release against pgpool-II 3.3.9.

    __________________________________________________________________

* Bug fixes

    - Removing the limit on the maximum number of items in the
      black_function_list and white_function_list lists. (Muhammad Usama)

      extract_string_tokens in pool_config uses the fixed size malloc on
      the array to hold the black_function_list/white_function_list items.
      This imposes a limit of maximum items in these lists.
      The fix is to use realloc to increase the array size when it gets full.

    - Redirect all user queries to primary server (Tatsuo Ishii)

      Up to now some user queries are sent to other than the primary server
      even if load_balance_mode = off. This commit changes the behavior: if
      load_balance_mode = off in streaming replication mode, now all the
      user queries are sent to the primary server only.

      Per bug #189.

    - Change the PID length of pcp_proc_count command result to 6 characters
      long (Bo Peng)

      If the pgpool process ID are over 5 characters, the 6th character of each
      process ID will be removed. This commit changes the process ID length of
      pcp_proc_count command result to 6 characters long.

      Per bug #188.

===============================================================================

                        3.3.9 (tokakiboshi) 2016/04/04

* Version 3.3.9

    This is a bugfix release against pgpool-II 3.3.8.

    __________________________________________________________________

* Bug fixes

    - test: Fix test/regression/clean.sh to remove binary files of
      010.rewrite_timestamp test (Yugo Nagata)

    - Fix memory leak reported by Coverity (CID 1350095) (Yugo Nagata)

    - Fixing pgpool-recovery module compilation issue with PostgreSQL 9.6
      (Muhammad Usama)

      Incorporating the change of function signature for GetConfigOption..()
      functions in PostgreSQL 9.6.

    - Fix typo in configure (Tatsuo Ishii)

      Patch provided by Thomas Munro.

    - doc: Change description of backend_flag (Tatsuo Ishii)

      It is pointed out that restarting pgpool-II is not necessary.

      Per [pgpool-general-jp: 1394].

    - doc: Fix installation procedure. (Tatsuo Ishii)

      With PostgreSQL 9.4 or later, installing pgpool_regclass is not needed.

    - test: Fix pgpool_setup to not confuse log output (Tatsuo Ishii)

      Before it simply redirects stdout and stderr of pgpool processes to
      a log file. This could cause the log contents being garbled or even
      missed because of race condition caused by multiple process being
      writing concurrently.

      To fix this, pgpool_setup now generates startall script in which pgpool
      sends stdout/stderr to cat command by pipe, and cat writes to the log
      file.

    - Fix to validate the PCP packet length (Muhammad Usama)

      Without the validation check, a malformed PCP packet can crash the
      PCP child and/or can run the server out of memory by sending the packet
      with a very large data size.

    - Fix a reset query stuck problem (Muhammad Usama)

      The solution is to return  POOL_END_WITH_FRONTEND_ERROR instead of
      POOL_END when pool_flush on front-end socket fails.

      The original report is
      [pgpool-general: 4265] Pgpool - connection hangs in DISCARD ALL

===============================================================================

                        3.3.8 (tokakiboshi) 2016/02/05

* Version 3.3.8

    This is a bugfix release against pgpool-II 3.3.7.

    __________________________________________________________________

* Bug fixes

    - doc: Fix misinformation regarding load balancing in docs (Tatsuo Ishii)

      In streaming replication mode, DECLARE, FETCH, CLOSE and SHOW are sent
      to primary node only. Pointed out in [pgpool-general-jp: 1378].

    - Issue fsync() when writing pgpool_status (Tatsuo Ishii)

      This ensures that pgpool_status is saved to permanent storage and
      allow to survive after system crash.

    - test: Fix false alarm of regression tset 062 (Yugo Nagata)

    - test: Fix broken regression test for native replication (Yugo Nagata)

      Test for insert lock didn't work.

    - test: Fix regress test to sleep after pgpool_reload (Yugo Nagata)

      Some regression tests modify configuration file and reloads. However,
      sometimes these were not applied to pgpool just after reloading.

    - Fix inconsistency of sequence values in replication mode (Yugo Nagata)

      When a schema name was provided, the table name was quoted wrongly as
      like "public.mytbl" instead of "public"."mytbl". So, pool_regclass
      and to_regclass couldn't find right table oid and insert lock was
      never executed. This caused inconsistency between DB nodes.

    - test: Fix complication error and segfault of timestamp rewrite test
      (Yugo Nagata)

    - test: Add timestamp-rewrite unit test to regression test suite (Yugo Nagata)

    - Fix ancient bug of pool_push() and friends (Tatsuo Ishii)

      It allocates buffer using realloc and uses the pointer
      returned. However it does the pointer calculation *before* realloc
      gets called. So the calculation uses the old pointer value, which
      causes various problems including segfault later.

      Also there were other problems with it. The buffer pointer and buffer
      size variable is not initialized. The buffer is not freed by
      pool_close. Typo in debugging message (3.4 or later only). They are
      fixed as well.

    - doc: Fix wrong description about log_standby_delay in the document
      (Yugo Nagata)

    - test: Fix regression test 065 (Tatsuo Ishii)

      The path to JDBC driver was explicitly defined. This is wrong. This
      should be inherited from JDBC_DRIVER environment variable.

    - test: Add option to regress.sh and pgpool_setup for unix domain socket
      directory (Yugo Nagata)

    - doc: Add missing descriptions about default values to documents (Yugo Nagata)

    - test: Fix a bug of regress.sh option handling (Yugo Nagata)

    - test: Fix regression test 055.backend_all_down to use PGSOCKET_DIR for
      PostgreSQL rhel7 rpm (Yugo Nagata)

    - Fix bug with "SET TRANSACTION READ ONLY" (Tatsuo Ishii)

      Pgpool-II remembers that non read only queries (including SET) were
      executed in an explicit transaction and adds a "writing transaction"
      mark to the transaction. The mark affects the query routing behavior
      of pgpool-II while running in streaming replication mode. Pgpool-II
      starts sending queries to the primary after the mark is set. Because
      the effect of writing queries may appear on standbys after some delay
      in streaming replication mode, it is safer to route read queries to
      the primary after the mark is set.

      However there's oversight here. "SET TRANSACTION READ ONLY" does no
      data modification and should be treated as an exception.

      Per bug #157.

    - test: Fix to use timeout command to handle time out of regress test 062
      (Yugo Nagata)

    - test: Add missing \n in help messages (Yugo Nagata)

    - test: Fix regression test 003.failover for rhel7 postgresql rpm (Yugo Nagata)

      The expected result of 'show pool_nodes' is fixed to use
      PGSOCKET_DIR in hostname column.

    - Fix white/black_memqcache_table_list not require quotation (Yugo Nagata)

      The tables and schemas name specified in *_memqcache_table_list
      were needed to be quoted by double quotation.

      Patch contributed by Dang Minh Huong.
      Per [pgpool-hackers: 1323]

    - Fix FATAL error with reloading (Tatsuo Ishii)

      While reloading pgpool.conf, the number of DB nodes is tentatively set
      to 0, then counted up until reaching to the actual number of backends
      by the pgpool main process. Unfortunately the variable was on the
      shared memory and it confused pgpool child process when they were using
      the variable and this caused FATAL error.

      Per bug #156 report by harukat.

    - test: Add some tests for white/black_memqcache_table_list to regression
      test 006.memqcache (Yugo Nagata)

    - Add some warning messages for wd_authkey hash calculation failure
      (Yugo Nagata)

      Sometimes wd_authkey calculation fails for some reason other than
      authkey mismatch. The additional messages make these distinguishable
      for each other.

    - test: Fix regression test to check timeout of each test (Yugo Nagata)

    - test: Allow timeout value to be specified by the command option (Yugo Nagata)

    - Fix bugs with data modifying WITH clause. (Tatsuo Ishii)

      pgpool-II did not recognize the data modifying WITH clause despite
      pgpool-II 3.3 or after has SQL parser which recognizes it. The bug has
      been fixed in pgpool-II 3.5 (having PostgreSQL 9.5 parser), and the fix
      is back ported to pgpool-II 3.3 and 3.4.

      Per bug #153.

    - Fix broken arping_cmd configuration check(Muhammad Usama)

      wd_chk_setuid() function was bailing out with the NOTICE message as soon
      as it finds the setuid bit is not set on any configured network command
      and was ignoring the rest of configurations.

      Per bug #139.

    - doc: Add restriction about starting multiple pgpool simultaneously
      (Yugo Nagata)

    - Fix a in-memory query cache bug (Tatsuo Ishii)

      If extended query protocol is used and a bind/execute message arrives
      which uses a statement created by prior parse message, the temp_cache
      is not initialized by a parse messages. Thus messages are added to pre
      existing temp cache buffer which causes the trouble, that is, when the
      cached result returns, Data Row message and Command Complete message
      appeared twice.

      Per by bug #152.

    - Ignore close statement/portal request if they do not exist (Tatsuo Ishii)

      In this case just returns a close complete message to client.
      This is a back port of the following commit from pgpool-II 3.4:

      1a37e1c35bd8b6f10f524693bbcb7b51f73b4bf0

    - test: Fix port numbers in expected result of show pool_nodes (Yugo Nagata)

===============================================================================

                        3.3.7 (tokakiboshi) 2015/07/24

* Version 3.3.7

    This is a bugfix release against pgpool-II 3.3.6.

    __________________________________________________________________

* Bug fixes

    - Fix "cannot find xlog functions" error in pgpool-recovery
      (Muhammad Usama)

      The argument data type of PostgreSQL's pg_xlogfile_name() function
      has been changed from text to pg_lsn since PostgreSQL 9.4. And
      pgpool-recovery was still trying to locate the function by old
      signature.

    - Pass empty string parameters in failover command when pgpool-II
      does not have a value for any particular parameter (Muhammad Usama)

      Instead of omitting the values for the parameters when pgpool-II does
      not have any value for a particular parameter, it now passes an empty
      string to the failover command. This makes sure that failover script
      will always receive the exact number of expected parameters.

    - doc: Clarify load balancing condition (Tatsuo Ishii)

    - doc: Clarify description of pcp_promote_node (Tatsuo Ishii)

      It does not actually promote PostgreSQL standby.

    - doc: Fix outdated limitation description about load balancing using
      JDBC driver (Tatsuo Ishii)

      Even if autocommit is false, load balancing is possible in certain
      conditions.

    - Fix "select() system call interrupted" error (Tatsuo Ishii)

      The health check process complains above and then:

      ERROR:  failed to make persistent db connection
      DETAIL:  connection to host:"x.x.x.x:5432 failed

      However, the healthcheck triggers neither fail over nor retrying. So,
      except the annoying messages above, everything goes well. This could
      occur more easily if 1) num_init_children is big and 2) pgpool
      children go into idle state (no query arrived from client for
      child_life_time seconds).

      Original bug report is [pgpool-general: 3756] Connection Interrupted.
      Patch created by Tatsuo Ishii. Enhancement from Usama.

    - Fix the case when user table includes spaces (Tatsuo Ishii)

      For example if table names including spaces are used, pgpool-II cannot
      be handled correctly by the internal functions which access system
      catalogs and it results in SQL errors. Solution is, to always use
      delimited identifier.

      Per bug #136.
      http://www.pgpool.net/mantisbt/view.php?id=136

      Also see [pgpool-general: 3818].

    - Allow to use in-memory query cache size more than 4GB (Tatsuo Ishii)

      This should have been allowed since in memory query cache was born.

    - Do not send a query for checking insert lock in non replication mode
      with extended query (Tatsuo Ishii)

===============================================================================

                        3.3.6 (tokakiboshi) 2015/04/08

* Version 3.3.6

    This is a bugfix release against pgpool-II 3.3.5.

    __________________________________________________________________

* Bug fixes

    - rpm: Fix %tmpfiles_create to not be executed in RHEL/CentOS 6
      (Nozomi Anzai)

    - Fix to use void * type for receiving return value of thread function
      (Yugo Nagata)

      Previously int type was used and this could occur stack buffer
      overflow. This caused an infinity loop of ping error at bringing
      up or down VIP.

    - Fix to set SIGCHLD to SIG_DFL instead of SIG_IGN in watchdog processes
      (Yugo Nagata)

      When using waitpid, it isn't necessary to set SIGCHLD to SIG_IGN.
      Rather, it is harmful, and due to this it was regarded that ping
      command exited abnormally in error even when this succeeded.

    - Remove an unnecessary include directive (Yugo Nagata)

    - Enlarge POOLCONFIG_MAXDESCLEN to 80 (Tatsuo Ishii)

      This is used in show pool_status command and limits the length of
      parameter description.  Unfortunately recovery_timeout description is
      64 chars, which is 1 byte longer than former definition of the macro.

    - doc: Update document of condition for load balancing (Yugo Nagata)

      Load balancing is possible in an explicit transaction block
      even in replication mode since 3.3.0.

    - Support SSL certificate chains in the certificate file for incoming
      frontend connections (Muhammad Usama)

    - Use to_regclass if available in time stamp rewriting in replication
      mode (Tatsuo Ishii)

    - Fix a hang when an error occurs in a transaction block with
      replication mode (Yugo Nagata)

      When an error occurs at a backend node in a transaction block with
      replication mode, pgpool-II sends an invalid query to other
      backends to sync transaction states. However, previously, this was
      not sent to master node, and pgpool-II was waiting for master's
      response forever.

    - Fix a problem with pcp_detach_node about graceful node detach (Muhammad Usama)

      When graceful node detach is requested gracefully, pcp_detach_node should
      check if it is allowed to process detach_node command on the particular
      node before blocking the incoming connections and closing the existing
      connections.

    - doc: Update table and flowchart of where a query should be sent to
      (Yugo Nagata)

    - rpm: pgpool.service is required only in RHEL/CentOS 7 (Nozomi Anzai)

===============================================================================
                        3.3.5 (tokakiboshi) 2015/02/05

* Version 3.3.5

    This is a bugfix release against pgpool-II 3.3.4.

    __________________________________________________________________

* Bug fixes

    - doc: Describe explicitly that the number of slave nodes is not
      necessarily 1 (Tatsuo Ishii)

    - Fix occasional deadlock in failover with watchdog enabled
      (Muhammad Usama)

      per bug #105
      http://www.pgpool.net/mantisbt/view.php?id=105

    - Fix uninitialized variable (Tatsuo Ishii)

      Per Coverity 1234603.

    - doc: Fix missing release note entries in the previous release
      (Tatsuo Ishii)

    - test: Fix wait_for_pgpool_startup in pgpool_setup to use "postgres"
      database rather than "test" (Tatsuo Ishii)

      The test database may or may not exist and if it does not, it will
      always retry until timeout expired (20 seconds), and regression test
      takes unnecessary long.

    - Fix possible segmentation fault in query cache (Tatsuo Ishii)

    - RPM: Add to support for memcached. (Tatsuo Ishii)

    - test: Allow pgpool_setup to set configuration file directory by setting
      environment variable PGPOOLDIR (Tatsuo Ishii)

    - RPM: Rename RPM file (Yugo Nagata)

      Rename filename to include the RHEL version number like PostgreSQL's
      official RPM file. (e.g. pgpool-II-pg93-3.4.0-2pgdg.rhel6.x86_64.rpm)

    - Fix node id range check bug in trigger_failover_command(). (Tatsuo Ishii)

      The node id should be lower than NUM_BACKENDS. Probably harmless since
      callers never pass node ids greater or equal to NUM_BACKENDS.

    - test: Fix failover script of pgpool_setup to use absolute path to the
      database cluster (Tatsuo Ishii)

    - test: Add memory leak regression test (Tatsuo Ishii)

    - Fix ill signal behavior of SIGCHLD in exec_ifconfig() (Tatsuo Ishii)

      For some reason SIGCHLD was set to SIG_IGN *and* tries to wait
      child process which always fails because SIGCHLD is never delivered.
      Due to this "ifconfig up" fails when switching to watchdog master.

      See "[pgpool-general: 3310] for more details.

    - Allow $_IP_$ having address prefix in if_up_cmd and if_down_cmd
      (Muhammad Usama)

      Previously, it is assumed that "$_IP_$" keyword will always have a
      white space at the end, and when "$_IP_$" has address prefix (e.g.
      $_IP_$/24), this prefix was ignored.

      Per bug #122.
      http://www.pgpool.net/mantisbt/view.php?id=122

    - Allow "show pool_nodes" to print node ids having more than one digits
      (Muhammad Usama)

      Problem reported in [pgpool-general: 3374].

    - Fix occasional failure in regression test '004.watchdog' (Yugo Nagata)

      The patch provided by uehara in bug #127.
      http://www.pgpool.net/mantisbt/view.php?id=127

    - Restore SIGCHLD handler to its original after executing if_up/down_cmd
      (Yugo Nagata)

      Previously SIGCHLD was set to SIGIGN always after if_up/down_cmd.
      This led to a incorrect error handling of ping or other commands
      execution, and warning messages were output to log even when the
      command exited successfully.

    - RPM: Add pgpool.service for systemd in RHEL/CentOS 7 (Nozomi Anzai)

    - RPM: Split pgpool_regclass and pgpool_recovery as a separate extension
      package (Tatsuo Ishii)

      On PostgreSQL server, only the extension package is required, no pgpool
      full package is necessary.

      Per Andrew N Golovkov.

    - RPM: Fix wrong SSL configure option in the RPM spec file (Tatsuo Ishii)

      SSL enabling option is "--with-openssl=/usr" and this is wrong. This
      should be "--with-openssl".

      Per bug #115.
      http://www.pgpool.net/mantisbt/view.php?id=115

    - RPM: Change to use systemd if it is available and adopt to PostgreSQL 9.4
      (Nozomi Anzai)

    - Fix to disable debug mode by reloading config (Yugo Nagata)

      Per bug #114
      http://www.pgpool.net/mantisbt/view.php?id=114

===============================================================================

                        3.3.4 (tokakiboshi) 2014/09/05

* Version 3.3.4

    This is a bugfix release against pgpool-II 3.3.3.

    __________________________________________________________________

* Bug fixes

    - Fix a typo of pgpool.spec (Yugo Nagata)

    - Fix bug that worker child process keeps failing when there's no
      primary backend (Tatsuo Ishii)

      Problem identified and fix contributed by Junegunn Choi.

      See [pgpool-hackers: 471] for more details.

    - Close listen socket when smart shutdown request is made (Tatsuo Ishii)

      When smart shutdown process starts, pgpool children still listen on
      the port and clients can send further connection requests which fail
      in the end. Which is not only waste of time, but also prevents a load
      balancer which sits in front of pgpool from realizing the pgpool is
      going down.

      Problem analyzed and patch provided by Junegunn Choi in [pgpool-hackers
      474], and enhanced to take care not only inet domain socket but UNIX
      domain socket by Tatsuo Ishii.

    - doc: Add cautions that recovery commands are killed by statement_timeout
      of PostgreSQL. (Tatsuo Ishii)

    - test: Fix bug that wait_for_pgpool_startup does not work. (Tatsuo Ishii)

    - test: Fix test driver for watchdog to use wait_for_pgpool_startup correctly
      (Tatsuo Ishii)

    - Fix to ignore a harmless error code when executing ifconfig command
      (Yugo Nagata)

      When executing command such as ifconfig or ping by execv() in a forked
      child process, wait() can fails with an error code ECHILD, although the
      process exists exactly, if SIGCHLD is set to SIG_IGN in Linux. We should
      ignore this and not treat as failure of the command.

    - test: Add undocumented "-j" option to the script comment. (Tatsuo Ishii)

    - test: Fix unwanted JDBC regression test failure (Tatsuo Ishii)

    - test: Fix to prevent regression test failures on slow machines
      (Tatsuo Ishii)

    - test: Allow to specify PostgreSQL library directory by environment
      variable (Tatsuo Ishii)

    - Adopt PostgreSQL 9.4 having to_regclass (Tatsuo Ishii)

      PostgreSQL 9.4 has built-in function "to_regclass", which has
      equivalent functionality of pgpool_regclass. Now pgpool searches
      to_regclass first then try pgpool_regclass.

    - Fix unportable code related to SO_REUSEPORT (Tatsuo Ishii)

      There are several places using setsockopt(sock, SOL_SOCKET,
      SO_REUSEPORT...). SO_REUSEPORT is not available on all Linux kernels
      and the source code uses ifdef to detect the feature in the compile
      time. Problem is, the binary created with kernel which provides the
      feature cannot run on a kernel which does not provide the feature. Fix
      is, detecting the feature in the run time by checking error code
      returned by setsockopt() and ignore it if the cause of the error is
      lacking the feature.

    - doc: Remove old restriction description which is no longer true
      (Tatsuo Ishii)

    - Fix return type of text_to_lsn() function (Yugo Nagata)

      This caused compile warning.

    - Fix file descriptor leak when daemonize. (Tatsuo Ishii)

      Per Coverity 1111471.

    - Fix memory leak. (Tatsuo Ishii)

      Per Coverity 1111442.

    - Fix pgpool.init's long-standing bug of stop/restart failure
      (Yugo Nagata)

      In previous, pgpool.init uses killproc for stopping pgpool, but there
      are several problems. In the new version, "pgpool -m fast stop" is
      used in stop command.

      Original patch contributed by Ryan DeShone and modified by Yugo Nagata.

      See [pgpool-hackers: 239][pgpool-hackers: 512].

    - Allow to run pgpool_setup and regression test on Ubuntu box
      (Tatsuo Ishii)

    - test: Fix -i option (install directory of pgpool) not working
      (Tatsuo Ishii)

    - Add missing include file sys/wait.h. (Tatsuo Ishii)

      Per bug #104.
      http://www.pgpool.net/mantisbt/view.php?id=104

    - Fix an infinite loop of ping error at new active pgpool when virtual
      IP switching (Yugo Nagata)

      This bug also caused hangs of the old active pgpool, since this waits
      response from the new active pgpool, which is in the infinite loop and
      not able to respond.

      This problem is reported by Qian Peng in [pgpool-hackers: 520].

    - Disable statement_timeout of PostgreSQL while executing online recovery
      (Tatsuo Ishii)

      Online recovery may take very long time and user may enable statement
      timeout. To prevent online recovery canceled by statement timeout,
      disable statement timeout in the connection used by online recovery.

      See [pgpool-general: 2919] for more details.

    - Fix pool_table_name_to_oid in case new to_regclass used which is
      introduced in PostgreSQL 9.4 (Tatsuo Ishii)

      The relcache func used here should return 0 if target table is not
      found. However to_regclass returns NULL in this case. To fix the
      problem now COALESCE is used.

    - test: Fix regression test 057 hung if run against PostgreSQL 9.4 or
      later (Tatsuo Ishii)

      PostgreSQL 9.4 or later changed libpq behavior: NULL username for
      connection string does not cause an error, which was expected in the
      test.

    - Fix to close pipe when ping command exits with failure (Yugo Nagata)

      This bug causes pipe open error: Too many open files, which
      leads to failure of connecting to trusted servers, and then
      pgpool goes to down status.

    - Fix Resource leaks (Muhammad Usama)

      Coverity issue #1222998 and #1222999.

    - Add a description that pcp_detach_node command disconnects existing
      sessions (Tatsuo Ishii)

    - Fix failover.sh produced by pgpool_setup (Tatsuo Ishii)

      It did not support there's more than 2 nodes case. It always tries to
      promoto node0 or node1.

    - Remove meaningless minus check because of unsigned int variable
      (Tatsuo Ishii)

      Coverity issue #1111419, #1111420, #1111422.

    - replacing strcpy() with much safer and recommended call strlcpy()
      (Muhammad Usama)

      Coverity issue #1111480.

    - Fix pgpool.spec to support openssl (Tatsuo Ishii)

    - Fix pgpool.spec to use 3.3-stable tree head (Tatsuo Ishii)

    - Remove unnecessary call to pool_shmem_exit() which removes semaphore
      when it shouldn't (Tatsuo Ishii)

      exit_handler checks if the process is parent or not. This is
      good. However, even if it is a child process, it calls
      pool_shmem_exit() which removes semaphore and shmem when it should
      not. It should be called only from parent process.

      Per bug #102.
      http://www.pgpool.net/mantisbt/view.php?id=102

    - Fix get_insert_command_table_name() function not to use freed pointer
      (Muhammad Usama)

      Coverity issue #1223007.

    - Fix pool_handle_query_cache() to not free NULL pointer (Tatsuo Ishii)

    - Change connect() timeout longer (10 seconds) for flaky network
      (Tatsuo Ishii)

      Change connect() timeout in connect_inet_domain_socket_by_port() from
      1 second to 10 seconds for flaky network such as AWS. This should help
      reducing frequent failover.

    - Fix reset query stuck problem. (Tatsuo Ishii)

      It is reported that reset query (DISCARD ALL etc.) occasionally does
      not finish and pgpool child remain waiting for reply from backend thus
      client cannot connect to pgpool.

      The cause of problem is not identified yet but if client suddenly
      closes connection to pgpool in the middle of query processing, backend
      may not accept the reset queries because they are not ready for query.

      The fix is, if frontend closes connection in unexpected way, query
      process loop immediately returns with new state:
      POOL_END_WITH_FRONTEND_ERROR and pgpool closes connection to
      PostgreSQL then goes back to new connection request waiting loop.

      Also, pgpool closes connections to backend when client_idle_limit is
      set and the idle limit.

      Per bug #107.
      http://www.pgpool.net/mantisbt/view.php?id=107

    - Fix other dozens of coverity issues (Muhammad Usama)

===============================================================================

                        3.3.3 (tokakiboshi) 2014/03/24

* Version 3.3.3

    This is a bugfix release against pgpool-II 3.3.2.

    __________________________________________________________________

* Bug fixes

    - installer: Fix bug that install of pgpool-II RPM fails (Yugo Nagata)

    - installer: Fix to set up passwordless SSH from apache@localhost to
      postgres@localhost (Yugo Nagata)

    - Fix bug that restarted pgpool's watchdog status is regarded as down
      (Yugo Nagata)

    - doc: Add mention about "listen queue" and how to increase the "backlog"
      in the num_init_children section. (Tatsuo Ishii)

    - Fix bug that watchdog status goes down even when only one of trusted
      servers get unpingable (Yugo Nagata)

    - Fix bad performance of unlogged tables detection code. (Tatsuo Ishii)

      Pointed out at [pgpool-hackers: 435][[pgpool-general:2325].

    - Fix primary node detection logic. (Tatsuo Ishii)

      There's a possibility that primary node is not detected. This happens
      in following situation.  node 0: primary, node 1: standby. Node 0 goes
      down. Health checking detects the fact but local status is not updated
      yet. Primary node finding (find_primary_node) runs. Node 0's status is
      yet healthy. Because find_primary_node fails to connect to node 0, it
      immediately returns -1 and fails to find that fact that node 1 is now
      primary.

      Fix is just continuing to look for primary node when fails to connect
      to a node.

      Per [pgpool-general: 2409].

    - Add raw mode support to pgpool_setup. (Tatsuo Ishii)

    - test: Integrate jdbc test to regression test. (Tatsuo Ishii)

    - Fix jdbc DML fails when operated in raw mode and auto commit is off.
      (Tatsuo Ishii)

      This is reported in bug #92.

    - Fix to output error message when wd_escalation_command fails with exit
      code other than 0 (Yugo Nagata)

      This is suggested by Sergey Arlashin in [pgpool-general: 2457].

    - test: Add new regression test for query cache. (Tatsuo Ishii)

    - Fix query cache bug with extended protocol. (Tatsuo Ishii)

      SELECT retrieves outdated cache even DML was executed in an explicit
      transaction. The bug had been there since in memory query cache was
      born. Per [pgpool-general-jp: 1252].

    - Add missing entries "relcache_size" and "check_temp_table" to show
      pool_status (Tatsuo Ishii)

    - Fix to output error message when if_up_cmd fails. (Yugo Nagata)

      This is suggested by Sergey Arlashin in [pgpool-general: 2457].

    - Avoid to send queries to unrelated nodes in streaming replication mode.
      (Tatsuo Ishii)

      Pgpool-II sends certain queries, such as BEGIN, END and SET commands to
      all of DB nodes. However in streaming replication mode, only primary
      node and at most one standby node are only concerned (if primacy node
      is selected as the load balance node, only 1 node is concerned).

      See [pgpool-hackers: 464] for more details.

    - Fix possible buffer overrun problem and memory leak. (Tatsuo Ishii)

      Per Coverity 1111465 and 1111482.

    - Fix possible buffer overrun. (Tatsuo Ishii)

      Replace strcpy() with strlcpy(). Per Coverity report 1111478, 1111480,
      1111481.

    - Add debug messages for analyzing errors in if_up_cmd (Yugo Nagata)

    - Fix freeing NULL. (Tatsuo Ishii)

      Per Coverity 1111384.

    - Do not enable query cache on materialized views. (Tatsuo Ishii)

      Per bug #95.

    - Fix memory leak. (Tatsuo Ishii)

      Per Coverity 1111446.

    - Fix a segmentation fault in parallel mode with system_db_hostname is
      empty (Yugo Nagata)

    - Fix to output debug messages in processing pgpool.conf with -d option
      (Yugo Nagata)

      Previously, some debug messages in pool_get_config() ware not output
      even when -d option was used.

    - Fix JDBC exception of prepared statement including now() in
      replication mode (Yugo Nagata)

      With JDBC, when a prepared statement is executed more than
      PrepareThreshold times, the statement is named and Describe message
      is sent after Parse. With named statement, pgpool rewrite now() to
      parameter in replication mode. Hence, rewritten query has additional
      parameter than original. In this case, ParameterDescription message
      sent to frontend (response of Describe) should include OIDs of the
      same number os original query's parameters. Otherwize, JDBC throws
      ArrayIndexoutOfBoundsException.

      This is reported in [pgpool-general-jp: 1192].

    - Fix backend error of prepared statement about table which has column whose
      default value is now() in replication mode (Yugo Nagata)

      When pgpool parses a named prepared statement with default now(),
      timestamps are replaced to additional parameters. So, Bind message also
      should included additional parameter format codes. However, when the
      number of original parameter was one, pgpool didn't handle this. This
      caused a error like "incorrect binary data format in bind parameter 2".

    - test: Fix a bug of regression test of JDBC that shows OK even when
      this fails (Yugo Nagata)

    - test: Add a new regression test for JDBC's PrepareThreshold (Yugo Nagata)

    - doc: Add description about parallel mode doesn't support PREPARE (Yugo Nagata)

      Per bug #93

===============================================================================

                        3.3.2 (tokakiboshi) 2013/11/29

* Version 3.3.2

    This is a bugfix release against pgpool-II 3.3.1.

    __________________________________________________________________

* Bug fixes

    - Fix incorrect time stamp rewriting in replication mode for certain time
      zones. (Tatsuo Ishii)

      Time stamp rewriting calls "SELECT now()" to get current time.
      Unfortunately the buffer for the current time is too small for certain
      time zones such as "02:30". Note that non-30-minutes-time-zone such as
      "0900" does not reveal the problem. This explains why we haven't the bug
      report until today.

      Bug reported in [pgpool-general: 2113] and fix provided by Sean Hogan.
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002142.html

    - installer: Fix the way to specify pgpoolAdmin version in
      redhat/rpm_installer/getsources.sh. (Yugo Nagata)

    - Makefile: Replace pg_config by $(PG_CONFIG) in Makefiles so it can be
      overridden at build time when compiling for different PG major versions.
      (Tatsuo Ishii)

      Patch contributed by Christoph Berg ([pgpool-general: 2127]).
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002156.html

    - watchdog: Fix a warning/error when compiling with -Werror=format-security.
      (Tatsuo Ishii)

      Patch contributed by Christoph Berg ([pgpool-general: 2127]).
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002156.html

    - configure: Remove -lcompat because it confuses FreeBSD per bug#15.
      (Tatsuo Ishii)
      http://www.pgpool.net/mantisbt/view.php?id=15

    - Fix segfault when pgpool.conf does not set log_standby_delay.
      (Tatsuo Ishii)

      This is caused by wrong initialization for log_standby_delay in
      pool_config.l.
      Per bug#74. http://www.pgpool.net/mantisbt/view.php?id=74

    - doc: Modify descriptions about restrictions of parallel mode
      Multiple rows INSERT using VALUES are not supported in parallel mode.
      (Yugo Nagata)

    - Avoid calling find_primary_node_repeatedly() when standby node goes
      down. (Tatsuo Ishii)

      This will reduce the time to failover. Per bug #75, patch modified by
      Tatsuo Ishii. http://www.pgpool.net/mantisbt/view.php?id=75

    - Fix data inconsistency problem with native replication mode + extended
      protocol case. (Tatsuo Ishii)

      It is reported that concurrent INSERT using JDBC driver causes data
      difference among database node. This only happens following conditions
      are all met:

      1) Native replication mode
      2) Extended protocol used
      3) The portal created by parse message is reused by bind message
      4) autocommit is on
      5) SERIAL (sequence) is used

      Pgpool-II's parse message function knows it has to lock the target
      table when INSERT (plus #5) is issued by clients. Unfortunately bind
      message function did not know it. Once parse/bind/execute finishes,
      pgpool releases the lock obtained by parse because of #4. JDBC wants
      to reuse the portal and starts the cycle from bind message, which does
      not obtain lock. As as result, lock-free INSERT are floating around
      which causes data inconsistency of course.  The solution is, lock the
      table in bind phase.

      For this bind needs to issue LOCK in extended protocol. This was a little
      bit hard because the module (do_command()) to issue internal SQL command
      (other than SELECT) does not support extended protocol.
      To solve the problem do_query() is modified so that it accepts other than
      SELECT because it already accepts extended protocol.
      The modification is minimum and is only tested for the case called from
      insert_lock(). I do not recommend to replace every occurrence of
      do_command () with do_query() at this point.

      BTW the reason why the bug is not reported is, most users uses JDBC
      with auto commit = off. In this case, the lock obtained by parse persists
      until user explicitly issues commit or rollback.

      Per bug report by Steve Kuekes in [pgpool-general: 2142].
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002171.html

    - Fix memory allocation size bug in the code path of query cache.
      (Tatsuo  Ishii)

      In execute() memory allocation size is too small incertain case. No bug
      has been reported so far, but certainly this is a bug.

    - Fix occasional segfault in query cache + extended protocol.
      (Tatsuo Ishii)

      When the query is not "cache safe", bind_msg->param_offset was not set
      in Bind(). However, Execute() unconditionally uses bind_msg->param_offset
      to convert bind parameters to string so that they can be added to the
      cached query string and it causes segfault because bind_msg->param_offset
      is a garbage. Also logic bug to calculate bind_msg->param_offset is
      corrected.

      Per bug#76. http://www.pgpool.net/mantisbt/view.php?id=76

    - Avoid to run out free query cache hash index entry. (Tatsuo Ishii)

      If hash index entries are run out, pgpool-II cannot reuse old cache
      entry because pgpool-II always expects there's at least one empty hash
      index entry. To mitigate the problem, if free hash index entries are run
      out, look for victim cache block to reuse the hash index entry.

      Per bug #70. http://www.pgpool.net/mantisbt/view.php?id=70

    - installer: checkEnv() didn't do anything and always returned 0.
      (Nozomi Anzai)

    - Fix inappropriate shared memory allocation size for clock hand.
      (Tatsuo Ishii)

      The memory for clock hand was allocated as sizeof(pool_fsmm_clock_hand))
      which is 8 bytes long because the variable is declared as:

        static int *pool_fsmm_clock_hand;

      This is plain wrong. The memory size actually needed is only 4 bytes,
      which is sizeof(*pool_fsmm_clock_hand)). In other word, the bug allocated
      unnecessary 4 bytes, which did nothing bd for the execution of program.
      But a bug is a bug.

      Per coverity report "1111476 Wrong sizeof argument"

    - Fix "show pool_status" always shows memqcache_auto_cache_invalidation as
      0. (Tatsuo Ishii)
      Per bug #80. http://www.pgpool.net/mantisbt/view.php?id=80

    - Fix error message in read_password_packet(). (Tatsuo Ishii)

    - watchdog: Fix to pass big parameter by pointer instead of by value at
      some function. (Yugo Nagata)

    - Fix memory leak when SSL is requested. (Tatsuo Ishii)

      When SSL is requested, pgpool child retries to read start up packet.
      However it does not free the memory for previous start up packet.

      Per Coverity report "1111443 Resource".

    - Fix memory leak when do_query() fails in timestamp rewriting.
      (Tatsuo Ishii)

      For this purpose free_select_result() is changed to accept NULL argument.
      Per Coverity report "1111454, 1111455 Resource leak".

    - Fix load balance bug in replication mode. (Tatsuo Ishii)

      When load_balance_mode = off, SELECTs including writing function
      should be sent to all the DB nodes. Per [pgpool-general: 2221].
      http://www.sraoss.jp/pipermail/pgpool-general/2013-October/002250.html

      The bug was introduced in:
      http://git.postgresql.org/gitweb/?p=pgpool2.git;a=commitdiff;h=1ac45a28258074ea4d9d902aca016f970d31f311
      (3.3.1).

    - watchdog: Fix to put null character at end of ping result string used in
      watchdog. (Yugo Nagata)

    - Fix target node selection logic when "DEALLOCATE portal|statement".
      (Tatsuo Ishii)

      When "DEALLOCATE portal|statement" is used and last prepared statement or
      portal was not found, target node selection map is not set. Probably this
      is not actually harmful because prepared statement or portal was not found
      is an error case. The bug was there since day 0.

      Per Coverity report "1111491 Structurally dead code".

    - Fix range check bug of MAX_NUM_BACKENDS in corner case. (Tatsuo Ishii)

      MAX_NUM_BACKENDS is the allowed max number of DB nodes (128, at this
      point). In reality, probably no one ever tried more than 128 DB nodes
      and that's the reason why nobody noticed.

      Per Coverity report "1111429, 1111430 and 1111431 Out-of-bounds write".

    - Do not set/unset fronted connection info for dead backend. (Tatsuo Ishii)

      Per bug #82. http://www.pgpool.net/mantisbt/view.php?id=82

    - Fix that the script forgets to allow public access to pgpool_catalog.
      (Tatsuo Ishii)

      The bug prevents inserting data into user tables if pgpool_catalog is
      created in native replication mode.  The bug was there from day 1. I
      wonder why nobody noticed until today.
      Per [pgpool-general-jp: 1229].
      http://www.sraoss.jp/pipermail/pgpool-general-jp/2013-November/001228.html

    - doc: Add description that it is recommended to specify multiple servers
      to trusted_servers. (Yugo Nagata)

    - Fix uninitialized variable in error case in pool_do_auth().
      (Tatsuo Ishii)

      If there's no valid backend, pgpool will return garbage pid to frontend in
      auth phase. Actually because no backend is available, frontend will be
      disconnected later on. So this is harmless.
      Per Coverity report "1127331 Uninitialized scalar variable".

    - Fix to add node id range check when issue an error message using node
      id. (Tatsuo Ishii)
      Per Coverity report #1111433 "Out-of-bounds read".

    - Fix buffer overrun bug and resource leak bug of parse_copy_data().
      (Tatsuo Ishii)
      Per Coverity report 1111427 "Out-of-bounds write" and 1111453 "Resource
      leak".

    - Fix possible segfault in CopyDataRaws(). (Tatsuo Ishii)
      Coverity pointed out that if pool_get_id() returns an error, VALID_BACKEND
      will access out of array.
      Per Coverity report 1111413 "Memory - illegal accesses".

    - Fix query cache is enabled and protocol version = 2 case. (Tatsuo Ishii)

      When the protocol version = 2, we assume that session state is "idle".
      This is not feasible but no way. I recommend to not use query cache
      with protocol 2.
      Per Coverity report 1111488 "Uninitialized scalar variable".

    - Fix strftime() usage in pool_pools(). (Tatsuo Ishii)

      The buffer is not large enough as expected by the second parameter. This
      is not harmless because the format string will not produce longer result
      string than the buffer.
      Per Coverity report 1111426 "Out-of-bounds access".

    - RPM: Improved to specify the versions of pgpool-II and PostgreSQL in the.
      spec file. (Nozomi Anzai)

    - Fix resource leak in make_persistent_db_connection. (Tatsuo Ishii)

      For this purpose, new static function free_persisten_db_connection_memory
      is added.
      Per Coverity report #1111468.

    - Fix a bug that connection check to trusted servers fails when the RTT
      is very short. (Yugo Nagata)

    - Fix several small bug fixes detected by Coverity. (Tatsuo Ishii)

===============================================================================

                        3.3.1 (tokakiboshi) 2013/09/06

* Version 3.3.1

    This is a bugfix release against pgpool-II 3.3.0.

    __________________________________________________________________

* Bug fixes

    - Fix to add the regression test suite for making tar boll (Tatsuo Ishii)

      This isn't included in the tar ball of 3.3.0 release.

    - Fix watchdog test script in regression test (Tatsuo Ishii)

    - Fix a memory overrun bug (Tatsuo Ishii)

      This problem is pointed out in [pgpool-general: 1956] by Sean Hogan.

      [pgpool-general: 1956] memory overrun bug?
      http://www.sraoss.jp/pipermail/pgpool-general/2013-July/001984.html

    - Fix a compile error (Yugo Nagata)

    - Fix child process termination with sig abort when memory query cache
      is enabled (Tatsuo Ishii)

      This is due to double free bug that occurs when multiple bind/execute
      messages come after a parse message. When a parse messages comes, query
      context is created along with temp cache. The pointer to the temp cache
      is added to the temp cache array when the query executed. Subsequent
      bind messages uses the same temp cache pointer. This is the source of
      double free bug when the cache array discarded.

      This is reported in Bug track #68 by harukat.

      #68: child process termination with sigabort when memory_cache_enabled = on
      http://www.pgpool.net/mantisbt/view.php?id=68

    - Add some test cases to regression test (Tatsuo Ishii)

    - Fix typos of the document in installation of pgpool-recovery section.
      (Tatsuo Ishii)

    - Fix a typo of log message (Yugo Nagata)

    - Fix typos of the japanese document (Yugo Nagata)

    - Fix to send SELECT to master node only when load_balance_mode is off
      in replication mode (Tatsuo Ishii)

      When load_balance_mode is off in replication mode, SELECT queries
      should be sent to master node only, rather than sent to all nodes in
      an explicit transaction.

      This problem is reported in [pgpool-general: 2038] by Rypl Lukas.

      [pgpool-general: 2038] SELECT sent to both nodes in replication mode
      http://www.sraoss.jp/pipermail/pgpool-general/2013-August/002066.html

    - Fix pgpool_setup to work in standalone. (Tatsuo Ishii)

===============================================================================

                        3.3.0 (tokakiboshi) 2013/07/30

* Version 3.3.0

      This is the first version of pgpool-II 3.3 series.
      That is, a "major version up" from 3.2 series.

      __________________________________________________________________

* Incompatible changes

    - All the following are about watchdog.
      See "New features" section below for details of these changes.

      - Default monitoring method was changed from query mode to heartbeat mode.

      - Failover/failback commands are executed in only one pgpool-II.

      - In default, all the query caches on shared memory are cleared when
        standby pgpool-II escalates to active.

      - Database name, user name, and password used for monitoring other
        pgpool-II by query are specified by dedicated parameters.
        Previously, template1, recovery_user, and recovery_password are used.

      __________________________________________________________________

* New features

  ** Watchdog

    - Add a new monitoring method using heartbeat signal of UDP packet in
      lifecheck. (Yugo Nagata)

      You can select a method from either of two methods, "heartbeat" mode or
      "query" mode.

      The heartbeat mode is the new method. In this mode, watchdog monitors
      other pgpool-II process by using heartbeat signal. Watchdog receives
      heartbeat signals sent by other pgpool-II periodically. If there are no
      signal for a certain period, watchdog regards it as failure of the
      pgpool-II. For redundancy you can use multiple networks for heartbeat
      exchange between pgpool-IIs. This mode is default and recommended one.

      The query mode is the conventional method. In this mode, watchdog monitors
      pgpool-II's service rather than process. Watchdog sends queries to other
      pgpool-II and checks the response. Note that this method requires connections
      from other pgpool-IIs, so it would fail motoring if num_init_children isn't
      large enough. This mode is deprecated and left for backward compatibility.

      Add these new parameters:
          - wd_lifecheck_method
          - wd_heartbeat_port
          - wd_heartbeat_keepalive
          - wd_heartbeat_deadtime
          - heartbeat_destinationX
          - heartbeat_destination_portX
          - heartbeat_deviceX

    - Add interlocking mechanism of exclusive failover/failback command
      execution. (Yugo Nagata)

      When using multiple pgpool-IIs with watchdog enabled, failover commands
      (failover_command, failback_command, and follow_master_command) get
      executed only at one pgpool-II.

      Previously, these command got executed at all pgpool-IIs.

    - Add authentication mechanism for watchdog packet communication.
      (Yugo Nagata)

      Watchdog packets (include heartbeat signal) from pgpool-II with wrong
      authentication key are rejected. All pgpool-IIs must have the same key,
      which is specified wd_authkey parameter in pgpool.conf. pgpool-II with
      wrong authkey can't even start watchdog, because the startup packet is
      rejected by other pgpool-IIs.

    - Add clear_memqcache_on_escalation parameter. (Yugo Nagata)

      If this is on, all the query caches on shared memory are cleared when
      standby pgpool-II escalates to active.

      This is aimed to prevent the new active pgpool-II from using inconsistent
      query caches with the previous active.

    - Add wd_escalation_command parameter. (Yugo Nagata)

      This specifies command which is executed at escalation on the new active
      pgpool-II server. The timing is just before virtual IP is brought up.

    - Add parameters wd_lifecheck_dbname, wd_lifecheck_user, and
      wd_lifecheck_password. (Yugo Nagata)

      These parameters specify the database name, the user name, and password
      used in query mode lifecheck of watchdog . Previously, these are hard
      coded to use template1, recovery_user, and recovery_password.

    - When delegate_IP parameter is empty, virtual IP is neither brought up
      nor switched. (Yugo Nagata)

      This allows multi-master like configuration without virtual IP.

    - Add pcp_watchdog_info command (Yugo Nagata)

      This is PCP command for retrieving the watchdog status.

  ** Others

    - Import PostgreSQL 9.2 raw parser. (Nozomi Anzai, Tatsuo Ishii)

    - Add a tool called pgpool_setup to set up pgpool-II and PostgreSQL
      temporary installation in current directory for *testing* purpose.
      (Tatsuo Ishii)

      usage: pgpool_setup [-m r|s][-n num_clusters][--no-stop]
         -m s: create an installation as streaming replication mode.
         (the default)
         -m r: create an installation as native replication mode.
         -n num_clusters: create num_clusters PostgreSQL database cluster nodes
         -p base_port: specify base port. The first PostgreSQL node's port is
                       base_port. Second PostgreSQL node's port is base_port+1
                       ... nth PostgreSQL node's port is base_port+n-1, pgpool
                       port is base_port+n, pcp port is base_port+n+1.
         --no-stop: do not stop pgpool and PostgreSQL after the work

    - Support installation method using CREATE EXTENSION for pgpool-recovery
      and pgpool-regclass. (Tatsuo Ishii)

      Older installation method is still preserved.

      Note: extension names are "pgpool_recovery" and "pgpool_regclass", not
      "pgpool-recovery" and "pgpool-regclass" because letters are not
      convenient in using CREATE EXTENSION command (requires double quotes).

    - Add a function "pgpool_pgctl()" which enables to execute
      pg_ctl stop/restart/reload (except for start) by SQL. (Nozomi Anzai)

      $ psql sales -c "select pgpool_pgctl('reload', 'fast')";
       pgpool_pgctl
      --------------
       t
      (1 row)

      This function always ignores the actual result and returns 't', so the
      user can't know if pg_ctl succeeded or failed. To use this we have to set
      the custom variable for security which limits the users to execute pg_ctl
      who has the permission of data directory.

    - Add shell scripts to install pgpool-II and pgpoolAdmin by RPM.
      (Nozomi Anzai, Yugo Nagata)

      To make the installer package execute getsources.sh, and the directory
      named "work" will be created. And you rpmbuild each spec files in work/,
      put RPMs into work/installer and make tar ball of work/installer.
      The installer does not only install RPMs but also edit postgresql.conf,
      pgpool.conf, pg_hba.conf, recovery.conf and scripts for failover and
      online recovery.

      This assumes two-nodes configuration and the install script have to be
      executed in both nodes.

    - Add new parameter "search_primary_node_timeout".
      (Muhammad Usama, Tatsuo Ishii)

      The parameter specifies the maximum amount of time in seconds to
      search for a primary node when a failover scenario occurs. Patch
      contributed by Muhammad Usama.  Japanese doc and slight editing of
      English doc by Tatsuo Ishii.

    - Chinese tutorials for memqcache and watchdog. (Bambo Huang)

    - Add regression test suit. (Tatsuo Ishii)

      __________________________________________________________________

* Bug fixes

    - Consider timeout waiting for completion of failback request in on line
      recovery. (Tatsuo Ishii)

      This will prevent the situation that recovery operation continues forever
      and we cannot even shutdown pgpool-II main process. This could happen
      especially while executing follow master command.

    - Fix a bug that %H of follow_master_command is not assigned correctly the
      new primary node in stream replication mode.
      (Tatsuo Ishii)

    - Fix not to execute escalation when the pgpool-II which is already active
      receives down notification from other pgpool-II. (Yugo Nagata)

    - Fix wd_create_send_socket() not to execute select() before connect().
      (Yugo Nagata)

      How select() works on an unconnected socket is undefined, and differs
      between platform. On Linux, this returns 2 and it is eventually harmless.
      However, on Soraris, this returns 0 and it is indistinguishable from time
      timeout, so watchdog wouldn't work correctly.

    - Fix error when pgpool_regclass is not installed. (Tatsuo Ishii)

      The query used in pool_has_pgpool_regclass() fails if pgpool_regclass
      does not exist. The bug was introduced in 3.2.4.  See [pgpool-general:
      1722] for more details.

      [pgpool-general: 1722] [PgPool-II 3.2.4] pgpool_regclass now mandatory?
      http://www.sraoss.jp/pipermail/pgpool-general/2013-May/001749.html

    - Fix do_query() not to hang when PostgreSQL returns an error.
      (Tatsuo Ishii)

      The typical symptom is "I see SELECT is keep on running according to
      pg_stat_activity". To fix this pgpool-II just exits the process and
      kill the existing connection.  This is not gentle but at this point I
      believe this is the best solution.

    - Fix possible deadlock during failover with watchdog enabled.
      (Yugo Nagata)

      This is reported in Bug track #54 by arshu arora
      http://www.pgpool.net/mantisbt/view.php?id=54

    - Fix unnecessary degeneration caused by error on commit. (Tatsuo Ishii)

      In master slave mode, if master gets an error at commit, while other
      slaves are normal at commit, we don't need to degenerate any backend
      because it is likely that the "kind mismatch error" was caused by a
      deferred trigger.

    - Fix bug with do_query which causes hung in extended protocol.
      (Tatsuo Ishii)

      This problem could occur when insert lock is enabled and
      pgpool_catalog.insert_lock exists, See [pgpool-general: 1684] for more
      details.

      [pgpool-general: 1684] insert_lock hangs
      http://www.sraoss.jp/pipermail/pgpool-general/2013-May/001711.html

    - Fix possible failure of query cache invalidation for DML in transaction.
      (Tatsuo Ishii)

      CREATE TABLE t1(i INTEGER);
      CREATE TABLE t2(i INTEGER);
      SELECT * FROM t1;
      BEGIN;
      DELETE FROM t2 WHERE i = 0;
      INSERT INTO t1(i) VALUES(1);
      COMMIT;

      SELECT * FROM t1;

      At commit pgpool tries to delete cache for t2 but fails because
      there's no oid table entry for t2. Problem is, it fails to check oid
      table for t1. So cache for t1 remains and the last SELECT incorrectly
      returns cached data. Fix is, continuing to check oid table entries.

      This is reported in Bug track #58 by wms
      http://www.pgpool.net/mantisbt/view.php?id=58

    - Fix to register pgpool_regclass in pg_catalog schema (Tatsuo Ishii)

      This is necessary to deal with clients which restricts schema search path
      to pg_catalog only. Postgres_fdw is such a client.

    - Fix a hang of "pgpool -m f stop" (Tatsuo Ishii)

      This is caused by unmanaged pgpool children remaining. This could happen
      when multiple PostgreSQLs are going down or even when pgpool is started
      before PostgreSQL startup.

    - Fix a potential crash in pg_md5 command (Muhammad Usama)

    - Fix a segmentation fault that occurs when on memory query cache enabled
      and the query is issued in extended query mode and the result is too large
      (Tatsuo Ishii)

      This is reported in Bug track #63 by harukat.
      Analysis and a test case are also provided.

      #63 Child process was terminated by segmentation fault with memcached
      http://www.pgpool.net/mantisbt/view.php?id=63

    - Fix a segmentation fault of a child process that occurs when a startup
      packet has no PostgreSQL user information (Yugo Nagata)

      You can reproduce it by

          $ psql -p 9999 -U ''

      If enable_pool_hba is on, a child process terminates by segmentation
      fault. Otherwise if enable_pool_hba is off, the error message is

          ERROR: pool_discard_cp: cannot get connection pool for user (null)
                 database (null)

      In both cases, psql terminates with no message on frontend.

      In the fixed version, if PostgreSQL user is not specified in startup packet,
      the message as following is output to both log and frontend. This is
      the same behavior as PostgreSQL.

          FATAL: no PostgreSQL user name specified in startup packet

    - Fix memory allocation logic in extended query processing with on-memory
      query cache enabled (Tatsuo Ishii)

      When very long query string (> 1024 bytes) supplied in extended query
      with bind parameters, it fails to allocate enough memory.

    - Fix to verify the backend node number in pcp_recovery_node (Yugo Nagata)

      When an invalid number is used, null value is passed as an arguments
      of recovery script, and this causes a malfunction. In especially,
      rsync may delete unrelated files in basebackup scripts.

    - Fix a segmentation fault on main process that could occurs after backend
      error detection (Tatsuo Ishii)

      This is reported in Bug track #62 by tuomas.

      #62 Slave network outage causes a segmentation fault on main process
      http://www.pgpool.net/mantisbt/view.php?id=62

    - Fix bug with health check when used with child_life_time (Tatsuo Ishii)

      Failover could happen even if the backend was running fine.
      This problem is reported in [pgpool-general: 1892] by larisa sabban.

      [pgpool-general: 1892] Pgpool is unable to connect backend PostgreSQL
      http://www.sraoss.jp/pipermail/pgpool-general/2013-July/001920.html

    - Fix bug in parsing prepared statements with transaction handling in
      replication mode (Tatsuo Ishii)

      Parse() automatically starts a transaction for non SELECT query to keep
      consistency among nodes in replication mode. But this wasn't closed. If
      wrong query comes in, the transaction goes into an abort state but pgpool
      does not close the transaction. Thus next query causes error because the
      transaction is still in abort status.

      This problem was reported in [pgpool-general: 1877] by Sean Hogan.

      [pgpool-general: 1877] current transaction is aborted, commands ignored
      http://www.sraoss.jp/pipermail/pgpool-general/2013-July/001905.html

      __________________________________________________________________

* Enhancements

    - Add mention about "-D" option to the man page.
      (Tatsuo Ishii)

    - Fix to restart watchdog processes automatically when these exit abnormally.
      (Yugo Nagata)

    - Add more error checks and reportings to functions executing ping command
      with watchdog enabled. (Tatsuo Ishii)

    - Replace some unsafe functions, sprintf and strncpy, with more safe ones,
      snprintf and strlcpy respectively. (Yugo Nagata)

    - Replace "sticky bit" to "setuid bit" in log message, comments and
      function names. (Yugo Nagata)

      These words were used mistakenly and caused confusion.

    - Fix description on SSL in pool_hba.conf.sample. (Tatsuo Ishii)

    - Allow to load balancing in an explicit transaction in replication mode.
      (Tatsuo Ishii)

        The condition to allow the load balancing is as follows:
        1) replicate_select is off
        2) no writing functions are used
        3) transaction isolation level is not serializable
        4) no DML/DDL are issued in the transaction

    - Chinese manual is updated to the latest especially about watchdog. (Bambo Huang)

    - Add mention about "-D" option to the man page. (Tatsuo Ishii)

    - Move ssl_ca_cert and ssl_ca_cert_dir descriptions to the SSL section
      in the document (Yugo Nagata)

    - Add ssl_ca_cert and ssl_ca_cert_dir descriptions to the japanese document
      (Yugo Nagata)


===============================================================================
3.2 Series (2012/08/03 - )
===============================================================================

                        3.2.17 (namameboshi) 2016/08/31

* Version 3.2.17

    This is a bugfix release against pgpool-II 3.2.16.

    __________________________________________________________________

* Bug fixes

    - Fix buffer over run problem in "show pool_nodes". (Tatsuo Ishii)

      While processing "show pool_nodes", the buffer for hostname was too
      short. It should be same size as the buffer used for pgpool.conf.
      Problem reported by a twitter user who is using pgpool on AWS (which
      could have very long hostname).

    - Fix usage of wait(2) in pgpool main process. (Tatsuo Ishii)

      The usage of wait(2) in pgpool main could cause infinite wait in the
      system call. Solution is, to use waitpid(2) instead of wait(2).

    - Fix "kind mismatch" error message in pgpool. (Muhammad Usama)

      Many of "kind mismatch..." errors are caused by notice/warning
      messages produced by one or more of the DB nodes. In this case now
      Pgpool-II forwards the messages to frontend, rather than throwing the
      "kind mismatch..." error. This would reduce the chance of "kind
      mismatch..."  errors.

      See [pgpool-hackers: 1501] for more details.

    - Replace "MAJOR" macro to prevent occasional failure. (Tatsuo Ishii)

      The macro calls pool_virtual_master_db_node_id() and then access
      backend->slots[id]->con using the node id returned.  In rare cases, it
      could point to 0 (in case when the DB node is not connected), which
      gives access to con->major, then it causes a segfault.

      See bug 225 for related info.

    - doc : fix Japanese document typo. (Bo Peng)

    - Fixing a typo in the log message. (Muhammad Usama)

    - doc : Add comment to the document about connection_cache. (Tatsuo Ishii)

===============================================================================

                        3.2.16 (namameboshi) 2016/06/17

* Version 3.2.16

    This is a bugfix release against pgpool-II 3.2.15.

    __________________________________________________________________

* New features

    - Allow to access to pgpool while doing health checking (Tatsuo Ishii)

      Currently any attempt to connect to pgpool fails if pgpool is doing
      health check against failed node even if fail_over_on_backend_error is
      off because pgpool child first tries to connect to all backend
      including the failed one and exits if it fails to connect to a backend
      (of course it fails). This is a temporary situation and will be
      resolved before pgpool executes failover. However if the health check
      is retrying, the temporary situation keeps longer depending on the
      setting of health_check_max_retries and health_check_retry_delay. This
      is not good. Attached patch tries to mitigate the problem:

      - When an attempt to connect to backend fails, give up connecting to
      the failed node and skip to other node, rather than exiting the
      process if operating in streaming replication mode and the node is
      not primary node.

      - Mark the local status of the failed node to "down".

      - This will let the primary node be selected as a load balance node
      and every queries will be sent to the primary node. If there's other
      healthy standby nodes, one of them will be chosen as the load
      balance node.

      - After the session is over, the child process will suicide to not
      retain the local status.

* Bug fixes

    - Fix is_set_transaction_serializable() when
      SET default_transaction_isolation TO 'serializable'. (Bo Peng)

      SET default_transaction_isolation TO 'serializable' is sent to
      not only primary but also to standby server in streaming replication mode,
      and this causes an error. Fix is, in streaming replication mode,
      SET default_transaction_isolation TO 'serializable' is sent only to the
      primary server.

      See bug 191 for related info.

    - Fix Chinese documentation bug about raw mode (Yugo Nagata, Bo Peng)
      Connection pool is available in raw mode.

    - Fix confusing comments in pgpool.conf (Tatsuo Ishii)

    - Permit pgpool to support multiple SSL cipher protocols (Muhammad Usama)

      Currently TLSv1_method() is used to initialize the SSL context, that puts an
      unnecessary limitation to allow only TLSv1 protocol for SSL communication.
      While postgreSQL supports other ciphers protocols as well. The commit changes
      the above and initializes the SSLSession using the SSLv23_method()
      (same is also used by PostgreSQL). Because it can negotiate the use of the
      highest mutually supported protocol version and remove the limitation of one
      specific protocol version.

    - If statement timeout is enabled on backend and do_query() sends a (Tatsuo Ishii)
      query to primary node, and all of following user queries are sent to
      standby, it is possible that the next command, for example END, could
      cause a statement timeout error on the primary, and a kind mismatch
      error on pgpool-II is raised.

      This fix tries to mitigate the problem by sending sync message instead
      of flush message in do_query(), expecting that the sync message reset
      the statement timeout timer if we are in an explicit transaction. We
      cannot use this technique for implicit transaction case, because the
      sync message removes the unnamed portal if there's any.

      Plus, pg_stat_statement will no longer show the query issued by
      do_query() as "running".

      See bug 194 for related info.

    - Deal with the case when the primary is not node 0 in streaming replication mode. (Tatsuo Ishii)

      http://www.pgpool.net/mantisbt/view.php?id=194#c837 reported that if
      primary is not node 0, then statement timeout could occur even after
      bug194-3.3.diff was applied. After some investigation, it appeared
      that MASTER macro could return other than primary or load balance
      node, which was not supposed to happen, thus do_query() sends queries
      to wrong node (this is not clear from the report but I confirmed it in
      my investigation).

      pool_virtual_master_db_node_id(), which is called in MASTER macro
      returns query_context->virtual_master_node_id if query context
      exists. This could return wrong node if the variable has not been set
      yet. To fix this, the function is modified: if the variable is not
      either load balance node or primary node, the primary node id is
      returned.

    - change the Makefile under the directory src/sql/, that is proposed (Bo Peng)
      by [pgpool-hackers: 1611]

    - Fix a possible hang during health checking (Yugo Nagata)

      Health checking was hang when any data wasn't sent
      from backend after connect(2) succeeded. To fix this,
      pool_check_fd() returns 1 when select(2) exits with
      EINTR due to SIGALRM while health checking is performed.

      Reported and patch provided by harukat and some modification
      by Yugo. Per bug #204.

      backported from 3.4 or later;
      https://git.postgresql.org/gitweb/?p=pgpool2.git;a=commitdiff;h=ed9f2900f1b611f5cfd52e8f758c3616861e60c0

    - Fix bug with load balance node id info on shmem (Tatsuo Ishii)

      There are few places where the load balance node was mistakenly put on
      wrong place. It should be placed on: ConnectionInfo *con_info[child
      id, connection pool_id, backend id].load_balancing_node].  In fact it
      was placed on: *con_info[child id, connection pool_id,
      0].load_balancing_node].

      As long as the backend id in question is 0, it is ok. However while
      testing pgpool-II 3.6's enhancement regarding failover, if primary
      node is 1 (which is the load balance node) and standby is 0, a client
      connecting to node 1 is disconnected when failover happens on node
      0. This is unexpected and the bug was revealed.

      It seems the bug was there since long time ago but it had not found
      until today by the reason above.


===============================================================================

                        3.2.15 (namameboshi) 2016/04/26

* Version 3.2.15

    This is a bugfix release against pgpool-II 3.2.14.

    __________________________________________________________________

* Bug fixes

    - Removing the limit on the maximum number of items in the
      black_function_list and white_function_list lists. (Muhammad Usama)

      extract_string_tokens in pool_config uses the fixed size malloc on
      the array to hold the black_function_list/white_function_list items.
      This imposes a limit of maximum items in these lists.
      The fix is to use realloc to increase the array size when it gets full.

    - Redirect all user queries to primary server (Tatsuo Ishii)

      Up to now some user queries are sent to other than the primary server
      even if load_balance_mode = off. This commit changes the behavior: if
      load_balance_mode = off in streaming replication mode, now all the
      user queries are sent to the primary server only.

      Per bug #189.

    - Change the PID length of pcp_proc_count command result to 6 characters
      long (Bo Peng)

      If the pgpool process ID are over 5 characters, the 6th character of each
      process ID will be removed. This commit changes the process ID length of
      pcp_proc_count command result to 6 characters long.

      Per bug #188.

===============================================================================

                        3.2.14 (namameboshi) 2016/04/04

* Version 3.2.14

    This is a bugfix release against pgpool-II 3.2.13.

    __________________________________________________________________

* Bug fixes

    - doc: Change description of backend_flag (Tatsuo Ishii)

      It is pointed out that restarting pgpool-II is not necessary.

      Per [pgpool-general-jp: 1394].

    - doc: Fix installation procedure. (Tatsuo Ishii)

      With PostgreSQL 9.4 or later, installing pgpool_regclass is not needed.

    - Fix to validate the PCP packet length (Muhammad Usama)

      Without the validation check, a malformed PCP packet can crash the
      PCP child and/or can run the server out of memory by sending the packet
      with a very large data size.

    - Fix a reset query stuck problem (Muhammad Usama)

      The solution is to return  POOL_END_WITH_FRONTEND_ERROR instead of
      POOL_END when pool_flush on front-end socket fails.

      The original report is
      [pgpool-general: 4265] Pgpool - connection hangs in DISCARD ALL

===============================================================================

                        3.2.13 (namameboshi) 2016/02/05

* Version 3.2.13

    This is a bugfix release against pgpool-II 3.2.12.

    __________________________________________________________________

* Bug fixes

    - doc: Fix misinformation regarding load balancing in docs (Tatsuo Ishii)

      In streaming replication mode, DECLARE, FETCH, CLOSE and SHOW are sent
      to primary node only. Pointed out in [pgpool-general-jp: 1378].

    - Issue fsync() when writing pgpool_status (Tatsuo Ishii)

      This ensures that pgpool_status is saved to permanent storage and
      allow to survive after system crash.

    - Fix ancient bug of pool_push() and friends (Tatsuo Ishii)

      It allocates buffer using realloc and uses the pointer
      returned. However it does the pointer calculation *before* realloc
      gets called. So the calculation uses the old pointer value, which
      causes various problems including segfault later.

      Also there were other problems with it. The buffer pointer and buffer
      size variable is not initialized. The buffer is not freed by
      pool_close. Typo in debugging message (3.4 or later only). They are
      fixed as well.

    - doc: Fix wrong description about log_standby_delay in the document
      (Yugo Nagata)

    - Fix bug with "SET TRANSACTION READ ONLY" (Tatsuo Ishii)

      Pgpool-II remembers that non read only queries (including SET) were
      executed in an explicit transaction and adds a "writing transaction"
      mark to the transaction. The mark affects the query routing behavior
      of pgpool-II while running in streaming replication mode. Pgpool-II
      starts sending queries to the primary after the mark is set. Because
      the effect of writing queries may appear on standbys after some delay
      in streaming replication mode, it is safer to route read queries to
      the primary after the mark is set.

      However there's oversight here. "SET TRANSACTION READ ONLY" does no
      data modification and should be treated as an exception.

      Per bug #157.

    - Fix FATAL error with reloading (Tatsuo Ishii)

      While reloading pgpool.conf, the number of DB nodes is tentatively set
      to 0, then counted up until reaching to the actual number of backends
      by the pgpool main process. Unfortunately the variable was on the
      shared memory and it confused pgpool child process when they were using
      the variable and this caused FATAL error.

      Per bug #156 report by harukat.

    - doc: Add restriction about starting multiple pgpool simultaneously
      (Yugo Nagata)

    - Fix a in-memory query cache bug (Tatsuo Ishii)

      If extended query protocol is used and a bind/execute message arrives
      which uses a statement created by prior parse message, the temp_cache
      is not initialized by a parse messages. Thus messages are added to pre
      existing temp cache buffer which causes the trouble, that is, when the
      cached result returns, Data Row message and Command Complete message
      appeared twice.

      Per by bug #152.

    - Ignore close statement/portal request if they do not exist (Tatsuo Ishii)

      In this case just returns a close complete message to client.
      This is a back port of the following commit from pgpool-II 3.4:

      1a37e1c35bd8b6f10f524693bbcb7b51f73b4bf0

===============================================================================

                        3.2.12 (namameboshi) 2015/07/24

* Version 3.2.12

    This is a bugfix release against pgpool-II 3.2.11.

    __________________________________________________________________

* Bug fixes

    - Fix "cannot find xlog functions" error in pgpool-recovery
      (Muhammad Usama)

      The argument data type of PostgreSQL's pg_xlogfile_name() function
      has been changed from text to pg_lsn since PostgreSQL 9.4. And
      pgpool-recovery was still trying to locate the function by old
      signature.

    - Pass empty string parameters in failover command when pgpool-II
      does not have a value for any particular parameter (Muhammad Usama)

      Instead of omitting the values for the parameters when pgpool-II does
      not have any value for a particular parameter, it now passes an empty
      string to the failover command. This makes sure that failover script
      will always receive the exact number of expected parameters.

    - doc: Fix outdated limitation description about load balancing using
      JDBC driver (Tatsuo Ishii)

      Even if autocommit is false, load balancing is possible in certain
      conditions.

    - Allow to use in-memory query cache size more than 4GB (Tatsuo Ishii)

      This should have been allowed since in memory query cache was born.

    - Do not send a query for checking insert lock in non replication mode
      with extended query (Tatsuo Ishii)

===============================================================================

                        3.2.11 (namameboshi) 2015/04/08

* Version 3.2.11

    This is a bugfix release against pgpool-II 3.2.10.

    __________________________________________________________________

* Bug fixes

    - Fix to use void * type for receiving return value of thread function
      (Yugo Nagata)

      Previously int type was used and this could occur stack buffer
      overflow. This caused an infinity loop of ping error at bringing
      up or down VIP.

    - Fix to set SIGCHLD to SIG_DFL instead of SIG_IGN in watchdog processes
      (Yugo Nagata)

      When using waitpid, it isn't necessary to set SIGCHLD to SIG_IGN.
      Rather, it is harmful, and due to this it was regarded that ping
      command exited abnormally in error even when this succeeded.

    - Remove an unnecessary include directive (Yugo Nagata)

    - Enlarge POOLCONFIG_MAXDESCLEN to 80 (Tatsuo Ishii)

      This is used in show pool_status command and limits the length of
      parameter description.  Unfortunately recovery_timeout description is
      64 chars, which is 1 byte longer than former definition of the macro.

    - Support SSL certificate chains in the certificate file for incoming
      frontend connections (Muhammad Usama)

    - Fix a problem with pcp_detach_node about graceful node detach (Muhammad Usama)

      When graceful node detach is requested gracefully, pcp_detach_node should
      check if it is allowed to process detach_node command on the particular
      node before blocking the incoming connections and closing the existing
      connections.

===============================================================================
                        3.2.10 (namameboshi) 2015/02/05

* Version 3.2.10

    This is a bugfix release against pgpool-II 3.2.9.

    __________________________________________________________________

* Bug fixes

    - doc: Describe explicitly that the number of slave nodes is not
      necessarily 1 (Tatsuo Ishii)

    - Fix uninitialized variable (Tatsuo Ishii)

      Per Coverity 1234603.

    - doc: Fix missing release note entries in the previous release
      (Tatsuo Ishii)

    - Fix possible segmentation fault in query cache (Tatsuo Ishii)

    - Fix node id range check bug in trigger_failover_command(). (Tatsuo Ishii)

      The node id should be lower than NUM_BACKENDS. Probably harmless since
      callers never pass node ids greater or equal to NUM_BACKENDS.

    - Allow $_IP_$ having address prefix in if_up_cmd and if_down_cmd
      (Muhammad Usama)

      Previously, it is assumed that "$_IP_$" keyword will always have a
      white space at the end, and when "$_IP_$" has address prefix (e.g.
      $_IP_$/24), this prefix was ignored.

      Per bug #122.
      http://www.pgpool.net/mantisbt/view.php?id=122

    - Allow "show pool_nodes" to print node ids having more than one digits
      (Muhammad Usama)

      Problem reported in [pgpool-general: 3374].

    - Fix to disable debug mode by reloading config (Yugo Nagata)

      Per bug #114
      http://www.pgpool.net/mantisbt/view.php?id=114

===============================================================================

                        3.2.9 (namameboshi) 2014/09/05

* Version 3.2.9

    This is a bugfix release against pgpool-II 3.2.8.

    __________________________________________________________________

* Bug fixes

    - Fix a typo of pgpool.spec (Yugo Nagata)

    - Fix bug that worker child process keeps failing when there's no
      primary backend (Tatsuo Ishii)

      Problem identified and fix contributed by Junegunn Choi.

      See [pgpool-hackers: 471] for more details.

    - Close listen socket when smart shutdown request is made (Tatsuo Ishii)

      When smart shutdown process starts, pgpool children still listen on
      the port and clients can send further connection requests which fail
      in the end. Which is not only waste of time, but also prevents a load
      balancer which sits in front of pgpool from realizing the pgpool is
      going down.

      Problem analyzed and patch provided by Junegunn Choi in [pgpool-hackers
      474], and enhanced to take care not only inet domain socket but UNIX
      domain socket by Tatsuo Ishii.

    - doc: Add cautions that recovery commands are killed by statement_timeout
      of PostgreSQL. (Tatsuo Ishii)

    - doc: Remove old restriction description which is no longer true
      (Tatsuo Ishii)

    - Fix return type of text_to_lsn() function (Yugo Nagata)

      This caused compile warning.

    - Fix file descriptor leak when daemonize. (Tatsuo Ishii)

      Per Coverity 1111471.

    - Fix memory leak. (Tatsuo Ishii)

      Per Coverity 1111442.

    - Fix pgpool.init's long-standing bug of stop/restart failure
      (Yugo Nagata)

      In previous, pgpool.init uses killproc for stopping pgpool, but there
      are several problems. In the new version, "pgpool -m fast stop" is
      used in stop command.

      Original patch contributed by Ryan DeShone and modified by Yugo Nagata.

      See [pgpool-hackers: 239][pgpool-hackers: 512].

    - Add missing include file sys/wait.h. (Tatsuo Ishii)

      Per bug #104.
      http://www.pgpool.net/mantisbt/view.php?id=104

    - Disable statement_timeout of PostgreSQL while executing online recovery
      (Tatsuo Ishii)

      Online recovery may take very long time and user may enable statement
      timeout. To prevent online recovery canceled by statement timeout,
      disable statement timeout in the connection used by online recovery.

      See [pgpool-general: 2919] for more details.

    - Remove unnecessary call to pool_shmem_exit() which removes semaphore
      when it shouldn't (Tatsuo Ishii)

      exit_handler checks if the process is parent or not. This is
      good. However, even if it is a child process, it calls
      pool_shmem_exit() which removes semaphore and shmem when it should
      not. It should be called only from parent process.

      Per bug #102.
      http://www.pgpool.net/mantisbt/view.php?id=102

    - Fix reset query stuck problem. (Tatsuo Ishii)

      It is reported that reset query (DISCARD ALL etc.) occasionally does
      not finish and pgpool child remain waiting for reply from backend thus
      client cannot connect to pgpool.

      The cause of problem is not identified yet but if client suddenly
      closes connection to pgpool in the middle of query processing, backend
      may not accept the reset queries because they are not ready for query.

      The fix is, if frontend closes connection in unexpected way, query
      process loop immediately returns with new state:
      POOL_END_WITH_FRONTEND_ERROR and pgpool closes connection to
      PostgreSQL then goes back to new connection request waiting loop.

      Also, pgpool closes connections to backend when client_idle_limit is
      set and the idle limit.

      Per bug #107.
      http://www.pgpool.net/mantisbt/view.php?id=107

===============================================================================

                        3.2.8 (namameboshi) 2014/03/24

* Version 3.2.8

    This is a bugfix release against pgpool-II 3.2.7.

    __________________________________________________________________

* Bug fixes

    - doc: Add mention about "listen queue" and how to increase the "backlog"
      in the num_init_children section. (Tatsuo Ishii)

    - Fix bug that watchdog status goes down even when only one of trusted
      servers get unpingable (Yugo Nagata)

    - Fix bad performance of unlogged tables detection code. (Tatsuo Ishii)

      Pointed out at [pgpool-hackers: 435][[pgpool-general:2325].

    - Fix primary node detection logic. (Tatsuo Ishii)

      There's a possibility that primary node is not detected. This happens
      in following situation.  node 0: primary, node 1: standby. Node 0 goes
      down. Health checking detects the fact but local status is not updated
      yet. Primary node finding (find_primary_node) runs. Node 0's status is
      yet healthy. Because find_primary_node fails to connect to node 0, it
      immediately returns -1 and fails to find that fact that node 1 is now
      primary.

      Fix is just continuing to look for primary node when fails to connect
      to a node.

      Per [pgpool-general: 2409].

    - Fix jdbc DML fails when operated in raw mode and auto commit is off.
      (Tatsuo Ishii)

      This is reported in bug #92.

    - Fix query cache bug with extended protocol. (Tatsuo Ishii)

      SELECT retrieves outdated cache even DML was executed in an explicit
      transaction. The bug had been there since in memory query cache was
      born. Per [pgpool-general-jp: 1252].

    - Add missing entries "relcache_size" and "check_temp_table" to show
      pool_status (Tatsuo Ishii)

    - Avoid to send queries to unrelated nodes in streaming replication mode.
      (Tatsuo Ishii)

      Pgpool-II sends certain queries, such as BEGIN, END and SET commands to
      all of DB nodes. However in streaming replication mode, only primary
      node and at most one standby node are only concerned (if primacy node
      is selected as the load balance node, only 1 node is concerned).

      See [pgpool-hackers: 464] for more details.

    - Fix possible buffer overrun problem and memory leak. (Tatsuo Ishii)

      Per Coverity 1111465 and 1111482.

    - Fix possible buffer overrun. (Tatsuo Ishii)

      Replace strcpy() with strlcpy(). Per Coverity report 1111478, 1111480,
      1111481.

    - Fix freeing NULL. (Tatsuo Ishii)

      Per Coverity 1111384.

    - Do not enable query cache on materialized views. (Tatsuo Ishii)

      Per bug #95.

    - Fix memory leak. (Tatsuo Ishii)

      Per Coverity 1111446.

    - Fix a segmentation fault in parallel mode with system_db_hostname is
      empty (Yugo Nagata)

    - Fix to output debug messages in processing pgpool.conf with -d option
      (Yugo Nagata)

      Previously, some debug messages in pool_get_config() ware not output
      even when -d option was used.

    - Fix JDBC exception of prepared statement including now() in
      replication mode (Yugo Nagata)

      With JDBC, when a prepared statement is executed more than
      PrepareThreshold times, the statement is named and Describe message
      is sent after Parse. With named statement, pgpool rewrite now() to
      parameter in replication mode. Hence, rewritten query has additional
      parameter than original. In this case, ParameterDescription message
      sent to frontend (response of Describe) should include OIDs of the
      same number os original query's parameters. Otherwize, JDBC throws
      ArrayIndexoutOfBoundsException.

      This is reported in [pgpool-general-jp: 1192].

    - Fix backend error of prepared statement about table which has column whose
      default value is now() in replication mode (Yugo Nagata)

      When pgpool parses a named prepared statement with default now(),
      timestamps are replaced to additional parameters. So, Bind message also
      should included additional parameter format codes. However, when the
      number of original parameter was one, pgpool didn't handle this. This
      caused a error like "incorrect binary data format in bind parameter 2".

    - doc: Add description about parallel mode doesn't support PREPARE (Yugo Nagata)

      Per bug #93

===============================================================================

                        3.2.7 (tokakiboshi) 2013/12/06

* Version 3.2.7

    This is a bugfix release against pgpool-II 3.2.6.

    __________________________________________________________________

* Bug fixes

    - Fix incorrect time stamp rewriting in replication mode for certain time
      zones. (Tatsuo Ishii)

      Time stamp rewriting calls "SELECT now()" to get current time.
      Unfortunately the buffer for the current time is too small for certain
      time zones such as "02:30". Note that non-30-minutes-time-zone such as
      "0900" does not reveal the problem. This explains why we haven't the bug
      report until today.

      Bug reported in [pgpool-general: 2113] and fix provided by Sean Hogan.
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002142.html

    - Makefile: Replace pg_config by $(PG_CONFIG) in Makefiles so it can be
      overridden at build time when compiling for different PG major versions.
      (Tatsuo Ishii)

      Patch contributed by Christoph Berg ([pgpool-general: 2127]).
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002156.html

    - Remove -lcompat because it confuses FreeBSD per bug#15. (Tatsuo Ishii
      http://www.pgpool.net/mantisbt/view.php?id=15

    - Fix segfault when pgpool.conf does not set log_standby_delay.
      (Tatsuo Ishii)

      This is caused by wrong initialization for log_standby_delay in
      pool_config.l.
      Per bug#74. http://www.pgpool.net/mantisbt/view.php?id=74

    - doc: Modify descriptions about restrictions of parallel mode
      Multiple rows INSERT using VALUES are not supported in parallel mode.
      (Yugo Nagata)

    - Avoid calling find_primary_node_repeatedly() when standby node goes
      down. (Tatsuo Ishii)

      This will reduce the time to failover. Per bug #75, patch modified by
      Tatsuo Ishii. http://www.pgpool.net/mantisbt/view.php?id=75

    - Fix data inconsistency problem with native replication mode + extended
      protocol case. (Tatsuo Ishii)

      It is reported that concurrent INSERT using JDBC driver causes data
      difference among database node. This only happens following conditions
      are all met:

      1) Native replication mode
      2) Extended protocol used
      3) The portal created by parse message is reused by bind message
      4) autocommit is on
      5) SERIAL (sequence) is used

      Pgpool-II's parse message function knows it has to lock the target
      table when INSERT (plus #5) is issued by clients. Unfortunately bind
      message function did not know it. Once parse/bind/execute finishes,
      pgpool releases the lock obtained by parse because of #4. JDBC wants
      to reuse the portal and starts the cycle from bind message, which does
      not obtain lock. As as result, lock-free INSERT are floating around
      which causes data inconsistency of course.  The solution is, lock the
      table in bind phase.

      For this bind needs to issue LOCK in extended protocol. This was a little
      bit hard because the module (do_command()) to issue internal SQL command
      (other than SELECT) does not support extended protocol.
      To solve the problem do_query() is modified so that it accepts other than
      SELECT because it already accepts extended protocol.
      The modification is minimum and is only tested for the case called from
      insert_lock(). I do not recommend to replace every occurrence of
      do_command () with do_query() at this point.

      BTW the reason why the bug is not reported is, most users uses JDBC
      with auto commit = off. In this case, the lock obtained by parse persists
      until user explicitly issues commit or rollback.

      Per bug report by Steve Kuekes in [pgpool-general: 2142].
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002171.html

    - Fix memory allocation size bug in the code path of query cache.
      (Tatsuo  Ishii)

      In execute() memory allocation size is too small incertain case. No bug
      has been reported so far, but certainly this is a bug.

    - Fix occasional segfault in query cache + extended protocol.
      (Tatsuo Ishii)

      When the query is not "cache safe", bind_msg->param_offset was not set
      in Bind(). However, Execute() unconditionally uses bind_msg->param_offset
      to convert bind parameters to string so that they can be added to the
      cached query string and it causes segfault because bind_msg->param_offset
      is a garbage. Also logic bug to calculate bind_msg->param_offset is
      corrected.

      Per bug#76. http://www.pgpool.net/mantisbt/view.php?id=76

    - Avoid to run out free query cache hash index entry. (Tatsuo Ishii)

      If hash index entries are run out, pgpool-II cannot reuse old cache
      entry because pgpool-II always expects there's at least one empty hash
      index entry. To mitigate the problem, if free hash index entries are run
      out, look for victim cache block to reuse the hash index entry.

      Per bug #70. http://www.pgpool.net/mantisbt/view.php?id=70

    - Fix inappropriate shared memory allocation size for clock hand.
      (Tatsuo Ishii)

      The memory for clock hand was allocated as sizeof(pool_fsmm_clock_hand))
      which is 8 bytes long because the variable is declared as:

        static int *pool_fsmm_clock_hand;

      This is plain wrong. The memory size actually needed is only 4 bytes,
      which is sizeof(*pool_fsmm_clock_hand)). In other word, the bug allocated
      unnecessary 4 bytes, which did nothing bd for the execution of program.
      But a bug is a bug.

      Per coverity report "1111476 Wrong sizeof argument"

    - Fix "show pool_status" always shows memqcache_auto_cache_invalidation as
      0. (Tatsuo Ishii)
      Per bug #80. http://www.pgpool.net/mantisbt/view.php?id=80

    - Fix error message in read_password_packet(). (Tatsuo Ishii)

    - watchdog: Fix to pass big parameter by pointer instead of by value at
      some function. (Yugo Nagata)

    - Fix memory leak when SSL is requested. (Tatsuo Ishii)

      When SSL is requested, pgpool child retries to read start up packet.
      However it does not free the memory for previous start up packet.

      Per Coverity report "1111443 Resource".

    - Fix memory leak when do_query() fails in timestamp rewriting.
      (Tatsuo Ishii)

      For this purpose free_select_result() is changed to accept NULL argument.
      Per Coverity report "1111454, 1111455 Resource leak".

    - watchdog: Fix to put null character at end of ping result string used in
      watchdog. (Yugo Nagata)

    - Fix target node selection logic when "DEALLOCATE portal|statement".
      (Tatsuo Ishii)

      When "DEALLOCATE portal|statement" is used and last prepared statement or
      portal was not found, target node selection map is not set. Probably this
      is not actually harmful because prepared statement or portal was not found
      is an error case. The bug was there since day 0.

      Per Coverity report "1111491 Structurally dead code".

    - Fix range check bug of MAX_NUM_BACKENDS in corner case. (Tatsuo Ishii)

      MAX_NUM_BACKENDS is the allowed max number of DB nodes (128, at this
      point). In reality, probably no one ever tried more than 128 DB nodes
      and that's the reason why nobody noticed.

      Per Coverity report "1111429, 1111430 and 1111431 Out-of-bounds write".

    - Do not set/unset fronted connection info for dead backend. (Tatsuo Ishii)

      Per bug #82. http://www.pgpool.net/mantisbt/view.php?id=82

    - Fix that the script forgets to allow public access to pgpool_catalog.
      (Tatsuo Ishii)

      The bug prevents inserting data into user tables if pgpool_catalog is
      created in native replication mode.  The bug was there from day 1. I
      wonder why nobody noticed until today.
      Per [pgpool-general-jp: 1229].
      http://www.sraoss.jp/pipermail/pgpool-general-jp/2013-November/001228.html

    - Fix uninitialized variable in error case in pool_do_auth().
      (Tatsuo Ishii)

      If there's no valid backend, pgpool will return garbage pid to frontend in
      auth phase. Actually because no backend is available, frontend will be
      disconnected later on. So this is not harmless.
      Per Coverity report "1127331 Uninitialized scalar variable".

    - Fix to add node id range check when issue an error message using node
      id. (Tatsuo Ishii)
      Per Coverity report #1111433 "Out-of-bounds read".

    - Fix buffer overrun bug and resource leak bug of parse_copy_data().
      (Tatsuo Ishii)
      Per Coverity report 1111427 "Out-of-bounds write" and 1111453 "Resource
      leak".

    - Fix possible segfault in CopyDataRaws(). (Tatsuo Ishii)
      Coverity pointed out that if pool_get_id() returns an error, VALID_BACKEND
      will access out of array.
      Per Coverity report 1111413 "Memory - illegal accesses".

    - Fix query cache is enabled and protocol version = 2 case. (Tatsuo Ishii)

      When the protocol version = 2, we assume that session state is "idle".
      This is not feasible but no way. I recommend to not use query cache
      with protocol 2.
      Per Coverity report 1111488 "Uninitialized scalar variable".

    - Fix strftime() usage in pool_pools(). (Tatsuo Ishii)

      The buffer is not large enough as expected by the second parameter. This
      is not harmless because the format string will not produce longer result
      string than the buffer.
      Per Coverity report 1111426 "Out-of-bounds access".

    - Fix resource leak in make_persistent_db_connection. (Tatsuo Ishii)

      For this purpose, new static function free_persisten_db_connection_memory
      is added.
      Per Coverity report #1111468.

    - Fix a bug that connection check to trusted servers fails when the RTT
      is very short. (Yugo Nagata)

    - Fix several small bug fixes detected by Coverity. (Tatsuo Ishii)

===============================================================================

                        3.2.6 (namameboshi) 2013/09/06


* Version 3.2.6

    This is a bugfix release against pgpool-II 3.2.5.

    __________________________________________________________________

* Bug fixes

    - Fix a segmentation fault on main process that could occurs after backend
      error detection (Tatsuo Ishii)

      This is reported in Bug track #62 by tuomas.

      #62 Slave network outage causes a segmentation fault on main process
      http://www.pgpool.net/mantisbt/view.php?id=62

    - Fix a bug with health check when used with child_life_time (Tatsuo Ishii)

      Failover could happen even if the backend was running fine.
      This problem is reported in [pgpool-general: 1892] by larisa sabban.

      [pgpool-general: 1892] Pgpool is unable to connect backend PostgreSQL
      http://www.sraoss.jp/pipermail/pgpool-general/2013-July/001920.html

    - Fix "Deploying pgpool-II" section in the document (Tatsuo Ishii)

      Update descriptions about watchdog use.

    - Fix a mistake in ssh command of doc/basebackup.sh (Tatsuo Ishii)

    - Fix a bug in parsing prepared statements with transaction handling in
      replication mode (Tatsuo Ishii)

      Parse() automatically starts a transaction for non SELECT query to keep
      consistency among nodes in replication mode. But this wasn't closed. If
      wrong query comes in, the transaction goes into an abort state but pgpool
      does not close the transaction. Thus next query causes error because the
      transaction is still in abort status.

      This problem was reported in [pgpool-general: 1877] by Sean Hogan.

      [pgpool-general: 1877] current transaction is aborted, commands ignored
      http://www.sraoss.jp/pipermail/pgpool-general/2013-July/001905.html

    - Fix child process termination with sig abort when memory query cache
      is enabled (Tatsuo Ishii)

      This is due to double free bug that occurs when multiple bind/execute
      messages come after a parse message. When a parse messages comes, query
      context is created along with temp cache. The pointer to the temp cache
      is added to the temp cache array when the query executed. Subsequent
      bind messages uses the same temp cache pointer. This is the source of
      double free bug when the cache array discarded.

      This is reported in Bug track #68 by harukat.

      #68: child process termination with sigabort when memory_cache_enabled = on
      http://www.pgpool.net/mantisbt/view.php?id=68

    - Fix typos of the japanese document (Yugo Nagata)

===============================================================================

                        3.2.5 (namameboshi) 2013/07/10

* Version 3.2.5

      This is a bugfix release against pgpool-II 3.2.4.

      __________________________________________________________________

* Bug fixes

    - Add mention about "-D" option to the man page. (Tatsuo Ishii)

    - Consider timeout waiting for completion of failback request in on line
      recovery (Tatsuo Ishii)

      This will prevent the situation that recovery operation continues forever
      and we cannot even shutdown pgpool-II main process. This could happen
      especially while executing follow master command.

    - Fix a bug that %H of follow_master_command is not assigned correctly the
      new primary node in stream replication mode
      (Tatsuo Ishii)

    - Fix wd_create_send_socket() to not execute select() before connect()
      (Yugo Nagata)

      How select() works on an unconnected socket is undefined, and differs
      between platform. On Linux, this returns 2 and it is eventually harmless.
      However, on Soraris, this returns 0 and it is indistinguishable from time
      timeout, so watchdog wouldn't work correctly.

    - Fix error when pgpool_regclass is not installed (Tatsuo Ishii)

      The query used in pool_has_pgpool_regclass() fails if pgpool_regclass
      does not exist. The bug was introduced in 3.2.4.  See [pgpool-general:
      1722] for more details.

      [pgpool-general: 1722] [PgPool-II 3.2.4] pgpool_regclass now mandatory?
      http://www.sraoss.jp/pipermail/pgpool-general/2013-May/001749.html

    - Fix do_query() to not hang when PostgreSQL returns an error
      (Tatsuo Ishii)

      The typical symptom is "I see SELECT is keep on running according to
      pg_stat_activity". To fix this pgpool-II just exits the process and
      kill the existing connection.  This is not gentle but at this point I
      believe this is the best solution.

    - Fix possible deadlock during failover with watchdog enabled
      (Yugo Nagata)

      This is reported in Bug track #54 by arshu arora

      #54 pgpool-II semaphore lock problem
      http://www.pgpool.net/mantisbt/view.php?id=54

    - Fix bug with do_query which causes hung in extended protocol
      (Tatsuo Ishii)

      This problem could occur when insert lock is enabled and
      pgpool_catalog.insert_lock exists, See [pgpool-general: 1684] for more
      details.

      [pgpool-general: 1684] insert_lock hangs
      http://www.sraoss.jp/pipermail/pgpool-general/2013-May/001711.html

    - Fix unnecessary degeneration caused by error on commit (Tatsuo Ishii)

      In master slave mode, if master gets an error at commit, while other
      slaves are normal at commit, we don't need to degenerate any backend
      because it is likely that the "kind mismatch error" was caused by a
      deferred trigger.

    - Fix possible failure of query cache invalidation for DML in transaction
      (Tatsuo Ishii)

      CREATE TABLE t1(i INTEGER);
      CREATE TABLE t2(i INTEGER);
      SELECT * FROM t1;
      BEGIN;
      DELETE FROM t2 WHERE i = 0;
      INSERT INTO t1(i) VALUES(1);
      COMMIT;

      SELECT * FROM t1;

      At commit pgpool tries to delete cache for t2 but fails because
      there's no oid table entry for t2. Problem is, it fails to check oid
      table for t1. So cache for t1 remains and the last SELECT incorrectly
      returns cached data. Fix is, continuing to check oid table entries.

      This is reported in Bug track #58 by wms

      #58 query cache invalidation does not fire for multiple DML in transaction
      http://www.pgpool.net/mantisbt/view.php?id=58

    - Fix to register pgpool_regclass in pg_catalog schema (Tatsuo Ishii)

      This is necessary to deal with clients which restricts schema search path
      to pg_catalog only. Postgres_fdw is such a client.

    - Fix a potential crash in pg_md5 command (Muhammad Usama)

    - Fix a segmentation fault that occurs when on memory query cache enabled
      and the query is issued in extended query mode and the result is too large
      (Tatsuo Ishii)

      This is reported in Bug track #63 by harukat.
      Analysis and a test case are also provided.

      #63 Child process was terminated by segmentation fault with memcached
      http://www.pgpool.net/mantisbt/view.php?id=63

    - Fix a segmentation fault of a child process that occurs when a startup
      packet has no PostgreSQL user information (Yugo Nagata)

      You can reproduce it by

          $ psql -p 9999 -U ''

      If enable_pool_hba is on, a child process terminates by segmentation
      fault. Otherwise if enable_pool_hba is off, the error message is

          ERROR: pool_discard_cp: cannot get connection pool for user (null)
                 database (null)

      In both cases, psql terminates with no message on frontend.

      In the fixed version, if PostgreSQL user is not specified in startup packet,
      the message as following is output to both log and frontend. This is
      the same behavior as PostgreSQL.

          FATAL: no PostgreSQL user name specified in startup packet

    - Fix memory allocation logic in extended query processing with on-memory
      query cache enabled (Tatsuo Ishii)

      When very long query string (> 1024 bytes) supplied in extended query
      with bind parameters, it fails to allocate enough memory.

    - Move ssl_ca_cert and ssl_ca_cert_dir descriptions to the SSL section
      (Yugo Nagata)

    - Add ssl_ca_cert and ssl_ca_cert_dir descriptions to the japanese document
      (Yugo Nagata)

    - Fix to verify the backend node number in pcp_recovery_node (Yugo Nagata)

      When an invalid number is used, null value is passed as an arguments
      of recovery script, and this causes a malfunction. In especially,
      rsync may delete unrelated files in basebackup scripts.

===============================================================================

                        3.2.4 (namameboshi) 2013/04/26

* Version 3.2.4

      This is a bugfix release against pgpool-II 3.2.3.

      __________________________________________________________________

* Bug fixes

    - Fix connect_inet_domain_socket_by_port() to set more appropriate value
      for timeout parameter of select(2). (Tatsuo Ishii)

      Some platforms such as Solaris do not allow to specify too large
      microseconds timeout value (>=1000000). So divide the timeout value to
      seconds and microseconds.

    - Fix connect_inet_domain_socket_by_port() to not return as normal when
      interrupted by alarm. (Tatsuo Ishii)

      This confuses health checking because connect_inet_domain_socket_by_port()
      returns usable fd. This makes detecting errors in health checking longer.

      See the following for more details:

      [pgpool-general: 1458]
      health check timeout in pgpool-II-3.2.3
      http://www.pgpool.net/pipermail/pgpool-general/2013-March/001482.html

    - Fix long standing bug with timestamp rewriting code for processing
      extended protocol. (Tatsuo Ishii)

      Parse() allocate memory using palloc() while rewriting the parse
      message.  Problem is, the rewritten message was kept in the data which
      is managed by pool_create_sent_message() etc. The function assumes
      that all the data is in session context memory. However, palloc()
      allocates memory in query context of course, and gets freed later on
      when the query context disappears. And the function tries to free the
      memory as well, which causes various problems, including segfault and
      double free. To fix this, memory to store rewritten message is
      allocated using session context. The bug was there since pgpool-II 3.0
      was born.

      Problem analysis and patch contributed by Naoya Anzai.

      [pgpoolgenera-jp: 1146]. (in Japanese)
      http://www.pgpool.net/pipermail/pgpool-general-jp/2013-March/001145.html

    - Fix bug with md5 auth long user name handling. (Tatsuo Ishii)

      If user name is longer than 32 bytes, md5 authentication doesn't work.
      Problem reported in [pgpool-general: 1526] by Thomas Martin.

      [pgpool-general: 1526]
      [pgPool-II 3.2.3] MD5 authentication and username longer than 32 characters.
      http://www.pgpool.net/pipermail/pgpool-general/2013-March/001551.html

    - Fix to calculate replication delay only if standby server is behind from
      the primary server. (Yugo Nagata)

      When the primary server is behind from standby server, negative value of
      delay is calculated and the value is assigned to unsigned variable. It
      causes a log message informing negative replication delay. And what is
      worse, it also causes SELECT queries to be sent to the primary in load
      balance even though there are no replication delay in fact.

      The problem is reported and analyzed by Saitoh Hidenori in
      [pgpool-genera-jp: 1145].

      [pgpool-general-jp: 1145] (in Japanese)
      http://www.pgpool.net/pipermail/pgpool-general-jp/2013-March/001144.html

    - pgpool-recovery adopts PostgreSQL 9.3. (Tatsuo Ishii)

      Patch contributed by Asif Rehman. Slight editing by Tatsuo Ishii.

      [pgpool-hackers: 180]
      compile error in ppool-recovery
      http://www.pgpool.net/pipermail/pgpool-hackers/2013-April/000179.html

    - Fix pool_has_pgpool_regclass() to check execute privilege of
      pgpool_regclass(). (Tatsuo Ishii)

      Even though pgpool_regclass() exists, if pgpool cannot execute the
      function, the connection to backend hangs. You can reproduce the problem
      by just dropping  the execute privilege from pgpool_regclass and do some
      insert in native replication mode.

      The problem is reported in bugtrack #53.

      #53 pgpool_regclass hangs all connections
      Date:     2013-04-04 13:35
      Reporter: tmandke
      http://www.pgpool.net/mantisbt/view.php?id=53

    - Fix error message mistakes in detect_postmaster_down_error(). (Tatsuo Ishii)

      For example, "LOG: detect_stop_postmaster_error: detect_error error" is
      fixed to "LOG: detect_postmaster_down_error: detect_error error", and so on.

    - Remove root user check when watchdog is enabled. (Tatsuo Ishii)

      Per discussion [pgpool-general: 1627] Re: watchdog root requirement.

      [pgpool-general: 1627]
      Re: watchdog root requirement.
      http://www.pgpool.net/pipermail/pgpool-general/2013-April/001654.html

    - Fix bug with on memory query cache in handling UPDATE/DELETE with table
      alias. (Tatsuo Ishii)

      If UPDATE/DELETE is with table alias (UPDATE t1 AS foo...) pgpool thinks
      the table name is "t1 AS foo" and fails to invalidate query cache. This
      is caused by _outRangeVar() called from nodeToString() which generates a
      query string from RangeVar node in raw parse tree. The solution is removing
      "AS foo" part from the output of the string.

      Reported in bugtrack #56.

      #56 UPDATE with alias does not discard cache
      Date:     2013-04-18 17:33
      Reporter: harukat
      http://www.pgpool.net/mantisbt/view.php?id=56

===============================================================================

                        3.2.3 (namameboshi) 2013/02/18

* Version 3.2.3

      This is a bug fix release against pgpool-II 3.2.2. Main purpose
      of this release is to fix fatal problem with pgpool-II 3.2.2's
      health checking. If all of following conditions are met, pgpool
      main process disappeared and all client connections to pgpool-II
      hang forever when failover happens. And the only way to recover
      from it is, manually killing the pgpool child process and restart
      pgpool-II.

      - health checking is enabled

      - connecting method to PostgreSQL is TCP/IP, not UNIX domain
        socket(i.e. "backend_hostnameN" is not empty string)

      __________________________________________________________________

* Bug fixes

    - Fix connect_inet_domain_socket_by_port() bug introduced in
      3.2.2. (Tatsuo Ishii)

      When non blocking connect() reports EINPROGRESS or EALREADY, it
      calls select(2) to wait for read or write fd ready. However it
      mistakenly checks error condition using getsockopt(). It should
      be called when select() returns > 0, rather than 0. Because of
      this, connect_inet_domain_socket_by_port() could return
      succeeded fd even it actually failed.

      And what is worse, this health_check() mistakenly believes that
      backend is alive and tries to write to backend socket, which of
      course fails. This triggers to call notice_backend_error(),
      which sends SIGUSR1 signal to pgpool main's parent process. This
      will result in various weird things: for example, if you start
      pgpool from a shell, the signal kills the shell.  If you start
      pgpool in background, pgpool's parent is the process #1. As long
      as you started pgpool as non root, it's ok. Even if you start
      pgpool as root, init just reopens /dev/initctl by receiving
      SIGUSR1. These all annoying bugs have been there since pgpool
      was born. The connect_inet_domain_socket_by_port() bug just
      reveals it. To fix this, I modified notice_backend_error and
      child_exit() so that it does nothing when called from pgpool
      main process itself to prevent pgpool from shooting itself in
      the foot.

    - Fix to show pool_passwd in "SHOW pool_status". (Yugo Nagata)

    - Fix a typo at configure's help in configure.in. (Yugo Nagata)

===============================================================================

                        3.2.2 (namameboshi) 2013/02/08

* Version 3.2.2

      This is a bugfix release against pgpool-II 3.2.1.

      __________________________________________________________________

* Bug fixes

    - Fix compile errors on FreeBSD. (Tatsuo Ishii)

    - Fix pgpool does not recognize VIEWs other than in default schema,
      which is usually "public". (Tatsuo Ishii)

      This makes pgpool to create caches for such a VIEW's query results,
      which of course should not be allowed.

      Problem reported and patch provided by jgentsch in bug id #30.

      #30 pgpool 3.2.1 - views in schema other than public are caching
      Reporter: jgentsch
      Date: 2012-10-19 23:13
      http://www.pgpool.net/mantisbt/view.php?id=30

    - Fix race condition when using md5 authentication. (Tatsuo Ishii)

      The file descriptor to pool_passwd is opened in pgpool main and pgpool
      child inherits it. When concurrent connections try to authenticate md5
      method, they call pool_get_passwd and seek the fd and cause random md5
      auth failure because underlying fd is shared. Fix is, let individual
      pgpool child open the file by calling pool_reopen_passwd_file.

      Problem reported and analyzed by Jason Slagle in pgpool-general:1141.

      [pgpool-general: 1141] Possible race condition in pool_get_passwd
      From: Jason Slagle
      Date: Sun, 28 Oct 2012 01:12:52 -0400
      http://www.sraoss.jp/pipermail/pgpool-general/2012-October/001160.html

    - Clarify load balance condition information in manual. (Tatsuo Ishii)

    - Fix segfault due to bug with query cache array handling. (Tatsuo Ishii)

      The cache array is used to keep temporary cache results in a transaction.
      If there are more than 128 SELECTs in a transaction, the module expands
      cache_array by using realloc. However it does not record the new pointer
      returned by realloc. So the module keeps on using the old pointer which is
      obsoleted.

      This problem is reported in bug track #31 by jgentsch.

      #31 pgpool V3_2_STABLE - segfault in pool_memqcache.c:2529
      Reporter:jgentsch
      Date: 2012-10-23 06:25
      http://www.pgpool.net/mantisbt/view.php?id=31

    - Fix hung up while repeating pcp_attach_node and pcp_detach_node
      (Tatsuo Ishii)

      When node status is changed by pcp_attach_node and pcp_detach_node,
      failover() sends SIGUSR1 to pcp_child process expecting it exits to
      refresh node status. In this situation lots of pgpool children exit and
      produce SIGCHLD as well. The SIGCHLD handler reaper() tries catch all
      SIGCHLD but sometimes it fails depending on the system load and timing.
      If SIGCHLD produced by pcp child is not caught, the process becomes
      zombie and never restarted.

      This problem is reported in bug track #32 (by oleg_myrk) etc.

      #32 PGPool hangs on pcp_attach/detach
      Reporter: oleg_myrk
      Date: 2012-10-24 00:01
      http://www.pgpool.net/mantisbt/view.php?id=32

    - Fix pool_send_severity_message() not to use uninitialized memory.
      (Tatsuo Ishii)

      It cause a segmentation fault.
      Reported in Bug #33's attached valgrind output by dudee.

      #33 pgpool-II 3.2.1 segfault
      Reporter: dudee
      Date: 2012-10-30 19:16
      http://www.pgpool.net/mantisbt/view.php?id=33

    - Fix bug with query cache returning incorrect data in some cases when a
      persistent table and temp table have same name. (Tatsuo Ishii)

      Here is a sequence to trigger the bug:

      1) CREATE TABLE t1(i int);    -- create a persistent table
      2) INSERT INTO t1 VALUES(1);
      3) SELECT * FROM t1;        -- query cache entry created
      4) CREATE TEMP TABLE t1(i int);    -- create a temp table
      5) SELECT * FROM t1;        -- query cache entry mistakenly created!

      Problem is #3 creates relcache entry for t1, and #5 incorrectly uses it
      and believes that temp table t1 is not a temp table.

    - Add a description about "-f" to help message. (Tatsuo Ishii)

    - Fix reaper() not to exit wait3() loop when catches pcp or worker child
      exit event. (Tatsuo Ishii)

      Otherwise reaper() mistakenly ignore some process exit event and make a
      risk of creating zombie process and forgetting to create new process.

      Problem reported and fix suggested by Goto in [pgpool-general-jp: 1123].
      http://www.sraoss.jp/pipermail/pgpool-general-jp/2012-November/001122.html
      (in Japanese)

    - Fix a typo of configure help message. (Yugo Nagata)

    - Add wd_hostname to pool_process_reporting.c. (Yugo Nagata)

      Otherwise, wd_hostname is not contained in results of SHOW pool_status and
      cp_pool_status.

    - Fix connect_inet_domain_socket_by_port() to not error out when connect(2)
      returns EISCONN (Socket is already connected) error. (Tatsuo Ishii)

      This could happen with non blocking socket and should be treated as normal.
      Per bug track #29 (by spork) and pgpool-general 1218 (by Mikola Rose).

      #29 pgpool 3.2.1 cannot connect to db hosts
      Reporter: spork
      Date: 2012-10-18 15:03
      http://www.pgpool.net/mantisbt/view.php?id=29

      [pgpool-general: 1218] pgpool 3.2.1 - Health check failing to connect
      From: Mikola Rose
      Date: Tue, 4 Dec 2012 20:21:55 +0000
      http://www.sraoss.jp/pipermail/pgpool-general/2012-December/001237.html

    - Fix health_check() to check the health check timer before retrying
      with template1 database. (Tatsuo Ishii)

      Without this, the retry with node 0 always fails because health check timer
      may be already expired.

    - Fix pool_search_relcache() to use MASTER or MASTER_NODE_ID macro, rather
      than REAL_MASTER_NODE_ID. (Tatsuo Ishii)

      In case node 0 fail back in streaming replication mode, pgpool does not
      restart child process.  So REAL_MASTER_NODE_ID looks for node 0 con info,
      which is not present until new connection to backend made. Thus referring
      to node con info results in segfault. MASTER or MASTER_NODE_ID are safe in
      this situation because they look at cached former master node id.

    - Fix long standing bug "portal not found" error when replication delay
      is too much in streaming replication mode. (Tatsuo Ishii)

      The bug had been there since the delay threshold was introduced.

      We changed destination DB node if delay threshold exceeds in bind,
      describe and execute. However, if parse sends to different node, bind,
      describe or execute will fail because no parsed statement or portal
      exists.  Solution is, not to send to different parse node even
      if delay threshold is too much.

    - Fix pg_md5 to output "\n" after user inputs password. (Yugo Nagata)

    - Fix to print error message when the port number for watchdog is already used.
      (Yugo Nagata)

      This issue was reported by Will Ferguson in [pgpool-general: 1167].

      [pgpool-general: 1167] Re: Watchdog error - wd_init: delegate_IP already exists
      From: Will Ferguson
      Date: Tue, 6 Nov 2012 13:03:36 +0000
      http://www.sraoss.jp/pipermail/pgpool-general/2012-November/001186.html

    - Fix child_exit() to not call send_frontend_exits() if there's no
      connection pool. (Tatsuo Ishii)

      Otherwise, it segfaults because send_frontend_exits() refers to objects
      pointed to by pool_connection_pool. Per bug track #44 by tuomas.

      #44 pgpool went haywire after slave shutdown triggering master failover
      Reporter: tuomas
      Date: 2012-12-11 00:33
      http://www.pgpool.net/mantisbt/view.php?id=44

    - Fix bug that only tables in white_memqcache_table_list was cached when
      black_memqcache_table_list has any tables. (Yugo Nagata)

    - Fix read_startup_packet() to reset alarm and free StartupPacket when
      pool_read() returns 0 which means incorrect packet length. (Nozomi Anzai)

      Previously, authentication timeout occurs when connected by a program
      monitoring the pgpool port.It is reported in bug track #35.

      #35 Authentication is timeout
      Reporter: tuomas
      Date: 2012-11-20 11:54
      http://www.pgpool.net/mantisbt/view.php?id=35

    - Fix long standing bug with pool_open(). (Tatsuo Ishii)

      It initializes wrong buffer pointer. Actually this is harmless because the
      pointer is initialized by prior memset() call, though.

    - Log that failover is avoided because "fail_over_on_backend_error" is
      turned off. (Tatsuo Ishii)

    - Fix LISTEN/NOTIFY handling bugs. (Tatsuo Ishii)

      1) In streaming replication mode:

      Session 1: LISTEN aaa;
      Session 2: NOTIFY aaa;
      Session 1: LISTEN aaa; --- hangs

      (If LISTEN and NOTIFY are issued in a same session, it works fine.)

      We assume that packets come from all nodes. However in streaming
      replication mode, notification message only comes from primary
      node and we should avoid reading from standby nodes.

      2) In streaming replication mode: If primary node is not node 0, it
      hangs like #1 even if fix applies. This is because MASTER_NODE_ID
      macro (actually pool_virtual_master_db_node_id()) always returns
      REAL_MASTER_NODE_ID, which is node 0 (if it is alive). The function
      should return PRIMARY_NODE_ID in master/slave mode.

      3) In replication mode, LISTEN/NOTIFY simply does not work.  In the
      mode, NOTIFY is sent to all backends.  However the order of arrival of
      'Notification response' is not necessarily the master first and then
      slaves.  So if it arrives slave first, we should try to read from
      master, rather than just discard it. Fixed in pool_process_query().

      4) In replication mode, if LISTEN and NOTIFY are issued in a same
      session, the session is disconnected because do_command() may receive
      other than 'N', 'E', 'S' and 'C'. The solution is, put 'A' packet on a
      stack and pop out when it is convenient. For this purpose, new
      functions pool_push(), pool_pop() and pool_stacklen() are added.

      This problem is reported in but grack #45 by rpashin.

      #45 LISTEN/NOTIFY doesn't work if cluster contains more then 1 node in
      streaming replication mode
      Reporter: rpashin
      Date: 2012-12-12 00:09
      http://www.pgpool.net/mantisbt/view.php?id=45

      Considering the size of the patch, I do not back patch to 3.1 or
      before(so far, we have not heard any complaints on 3.1 or before).

    - Fix connect_inet_domain_socket_by_port() to call select(2) rather than
      error out when connect(2) returns EINPROGESS or EALREADY error.
      (Tatsuo Ishii)

      When using non-blocking socket, despite the errors like
      "Connection timed out", actually connection has been established.
      To solve the problem we should use select(2) to wait for connection
      establishing when connect(2) reports EINPROGRESS or EALREADY, instead
      of doing a retry tight loop.

      This problem is reported in bug track #46 by mcousin.

      #46 Watchdog failing to connect sometimes
      Reporter: mcousin
      Date: 2012-12-15 01:01
      http://www.pgpool.net/mantisbt/view.php?id=46

    - Add caution to increase num_init_children if watchdog enabled in manual.
      (Tatsuo Ishii)

      See [pgpool-general: 1330] for more details.

      [pgpool-general: 1330] WatchDog and pgpool sudden stop working
      From: Tomas Halgas
      Date: Fri, 18 Jan 2013 14:47:23 +0100
      http://www.sraoss.jp/pipermail/pgpool-general/2013-January/001350.html

    - Fix segmentation fault while pgpool-II stating up or fail over when
      watchdog is enabled. (Yugo Nagata)

      This is caused by wrong usage of pthread, namely pthread_detach and
      pthread_join are mixed together.  Solution is to use pthread_join only
      if we need to get status of child thread. BTW, the problem could occu
      on moderately modern OS such as Fedora 17, but the reason why the problem
      is not observed on other OSs is, just we were lucky.

      Problem reported in [pgpool-general: 1179] by Lonni J Friedman.

      [pgpool-general: 1179] 3.2.1 segfaults at startup on Fedora17.
      From: Lonni J Friedman
      Date: Mon, 12 Nov 2012 15:58:29 -0800
      http://www.sraoss.jp/pipermail/pgpool-general/2012-November/001198.html

      Patch provided by chads in bug track #48.

      pthread_detach is being used wrong; causes pgpool to segfault.
      Reporter: chads
      Date: 2013-01-16 05:44
      http://www.pgpool.net/mantisbt/view.php?id=48

    - Avoid split-brain situation reported in [pgpool-general: 1046] (Yugo Nagata)

      After all backend nodes are detached from pgpools and then some backend node
      are attached to these, multiple active pgpools could exist simultaneously,
      that is to say, split-brain situation occurs.

      In this fix, when once all backend DB nodes are detached from pgpool, the pgpool
      stays DOWN status until this is restarted. The pgpool in DOWN status cannot
      escalate to active (delegate IP holder), so split-brain situation is avoided.

      [pgpool-general: 1046]
      watchdog enabled delegate_IP on multiple nodes simultaneously
      From: Lonni J Friedman
      Date: Wed, 26 Sep 2012 09:05:09 -0700
      http://www.sraoss.jp/pipermail/pgpool-general/2012-September/001064.html

    - Avoid a possible hang during the active pgpool exits. (Yugo Nagata)

      When exiting, the active pgpool brings down the virtual IP and then
      sends a packet to other pgpools. However, the packet sometimes is sent
      before the virtual IP is brought down completely. In this case the packet
      sender is set to this IP. When the IP is brought down before other pgpools
      respond, the active pgpool can not receive the response, and hang up.

      In this fix, the active pgpool confirms that the virtual IP is brought
      down before sending the packet.

    - Modify descriptions of restrictions on watchdog. (Yugo Nagata)

    - Modify pgpool.conf.sample* and documents to correct information of
      whether a certain parameter change requires restart. (Yugo Nagata)

    - Add pool_passwd option to pgpool.conf.sample*, pool_process_reporting.c,
      and documents. (Yugo Nagata)

      Otherwise, wd_hostname is not contained in results of SHOW pool_status and
      pcp_pool_status.

===============================================================================

                        3.2.1 (namameboshi) 2012/10/12

* Version 3.2.1

      This is a bugfix release against pgpool-II 3.2.0.

      __________________________________________________________________

* Bug fixes

    - Fix send_cached_messages(). (Tatsuo Ishii)

      Before it had 8192 bytes fix length buffer for each row data and if data
      exceeded 8192 bytes, it just crashed.
      To fix this, eliminate copying raw data which is passed as an argument
      to buffer and pass the pointer to send_message.

    - Fix that extended queries failed due to query cache. (Nozomi Anzai)

    - Fix read_startup_packet(). (Tatsuo Ishii)

      If packet length is lower than 0, it should have returned immediately.
      Otherwise it would cause memory allocation error later on.
      per pgpool-general:886. Also add canceling alarm.

      [pgpool-general: 886] read_startup_packet: out of memory
      From: Lonni J Friedman
      Date: Wed, 8 Aug 2012 10:18:15 -0700
      http://www.sraoss.jp/pipermail/pgpool-general/2012-August/000896.html

    - Fix too watchdog process's aggressively kill other processes when pgpool
      shuts down. (Tatsuo Ishii)

      watchdog process calls kill(0,SIG) to kill all processes related to
      watchdog.  Unfortunately this will kill not only watchdog related
      processes but parent pgpool and even httpd in case when pgpool was
      invoked from pgpoolAdmin because they are in the same process
      group.
      So for now, fix is removing call to the kill() and setpgid() because
      setpgid() does nothing useful.

      In the future, we should call setsid() to establish new process group
      in any case.

    - Fix query cache to regist such queries that start with "-- comment" or
      have comments more than one. (Nozomi Anzai)

    - Fix query cache to ignore multi statement. (Nozomi Anzai)

      In previous, queries like "SELECT 1;UPDATE..." were cached, too, but it
      was wrong.

    - Add a watchdog restriction to documents. (Yugo Nagata)

    - Add NOTICE message handling to s_do_auth(). (Tatsuo Ishii)

      Without this, health check responses false alarm and causes failover.
      per bug track:

      #25 s_do_auth doesn't handle NoticeResponse (N) message
      Date:     2012-08-28 03:57
      Reporter: singh.gurjeet
      Date:
      http://www.pgpool.net/mantisbt/view.php?id=25

    - Remove unnecessary/confusing debug log from s_do_auth().(Tatsuo Ishii)

    - Fix buffer overrun in Execute when memory cache enabled.
      (Tatsuo Ishii)

      If one of bind parameter < 0, it was possible to produce more than 2
      byte string for "%02X" due to sign extension.
      Also use snprintf, rather than sprintf to prevent from possible buffer
      overrun in the future.

    - Fix long standing memory leak bug with free_select_result() since
      pgpool-II 2.3 was born in December 2009. (Tatsuo Ishii)

      Actually this bug only appears when operated in replication mode
      (triggered by timestamp rewriting process by coincidence).
      Per bug track #24:

      #24 Severe memory leak in an OLTP environment
      Date:     2012-08-28 03:43
      Reporter: singh.gurjeet
      Date:
      http://www.pgpool.net/mantisbt/view.php?id=24

    - Fix typo in cache_reporting(). (Tatsuo Ishii)

    - Fix infinite loop in SSL mode.  (Tatsuo Ishii)

      When there's pending data in SSL layer of frontend, pool_process_query()
      checks pending data in backend. If there's non, it loops again and checks
      frontend/backend receive buffer by using is_cache_empty().
      Unfortunately it first checks pending data in SSL layer of frontend,
      thus goes to backend data and checks again (infinite loop).

      The solution is, if there's pending data in SSL layer of frontend and
      query is not in progress, call ProcessFrontendResponse() to process new
      request from frontend.

    - Fix is_system_catalog() to use pgpool_regclass if available.
      (Tatsuo Ishii)

    - Fix memory leak in pool_get_insert_table_name(). (Tatsuo Ishii)

      If session context's memory contex is used for nodeToString(), memory is
      not freed until session ends.
      See bug track #24 for more details.

      #24 Severe memory leak in an OLTP environment
      Date:     2012-08-28 03:43
      Reporter: singh.gurjeet
      http://www.pgpool.net/mantisbt/view.php?id=24

    - Use fcntl(2) rather than flock(2) to lock oid map files. (Tatsuo Ishii)

      flock(2) is not portable and cannot be used on Solaris.
      Patch contributed by Ibrar Ahmed.

    - Fix oversight of get_next_master_node() when operated in raw mode.
      (Tatsuo Ishii)

      If master node goes down, it always returned master node id 0.
      See [pgpool-general: 1039] for more details.

      [pgpool-general: 1039] Raw failover not working as expected on pgpool-II
      v3.2.0
      From: Quentin White
      Date: Tue, 25 Sep 2012 07:45:34 +0000
      http://www.sraoss.jp/pipermail/pgpool-general/2012-September/001057.html

    - Fix segfault of do_query(). (Tatsuo Ishii)

      When memqcache enabled and extended protocol is used, do_query()
      accesses system catalog and use pool_read2(). Unfortunately parse message
      packet is given to Parse() and the packet contents is on pool_read2's
      buffer. Thus do_query could break the packet contents, and it leads to
      segfault.

      Solution is, allocate memory and copies the packet contents and pass to
      Parse(). Note that query context holds query string, which is in the
      packet as well. So we need to copy it and save the pointer in the
      query context.

      We think the problem is not only with Parse() but with other protocol
      modules. So this fix is not Parse() only, rather for other modules. For
      this purpose ProcessFrontendResponse() is changed.

      See bugtrack in detail.

      #21 pgpool-II 3.2.0 cannot execute sql through jdbc
      Date:     2012-08-17 16:31
      Reporter: elisechiang
      http://www.pgpool.net/mantisbt/view.php?id=21

    - Fix to set unix domain socket path for pgpool PCP communication before
      setting up signal handlers. (Yugo Nagata)

      Previously, unlink of the socket in exiting process was failed because
      the path of the socket was not set.
      Patch contributed by Gilles Darold

      [pgpool-hackers: 131] Found bug with watchdog resulting in pgpool
                            segmentation fault
      From: Gilles Darold
      Date: Thu, 13 Sep 2012 18:54:42 +0200
      http://www.sraoss.jp/pipermail/pgpool-hackers/2012-September/000130.html

    - Fix to output the message when, in watchdog, ifup/down or arping command
      does not exist. (Yugo Nagata)

    - Fix long standing problem with do_query(). (Tatsuo Ishii)

      When 1) extended protocol used and 2)unnamed portal is used and 3) no
      explicit transaction is used, user's unnamed portal is removed by Sync
      message.
      This is because Sync message closes transaction and unnamed portal is
      removed. This leads to "portal "" does not exist" error.

      Fix is, use "Flush" message instead of Sync. Main difference between
      using Sync and Flush is, Flush does not return Ready for Query message.
      So do_query() does not return until all expected responses are returned.
      It seems the order of messages returned from backend is random, and
      do_query () manages it by using state bits.

===============================================================================

                        3.2.0 (namameboshi) 2012/08/03

* Version 3.2.0

      This is the first version of pgpool-II 3.2 series.
      That is, a "major version up" from 3.1 series.

      __________________________________________________________________

* Incompatible changes


    - The new query cache "On memory query cache" took the place of the old
      one.
      - Now the parameter "enable_query_cache" is deleted.

      __________________________________________________________________

* New features

  ** Memory based query cache

    Original author is Masanori Yamazaki, improved by Development Group.
   (Tatsuo Ishii, Nozomi Anzai, Yugo Nagata)

    Overview:

        On memory query cache is faster because cache storage is on memory.
        Moreover you don't need to restart pgpool-II when the cache is outdated
        because the underlying table gets updated.

        On memory cache saves pair of SELECT statements (with its Bind parameters
        if the SELECT is an extended query). If the same SELECTs comes in, it
        returns the value from cache. Since no SQL parsing nor access to
        PostgreSQL are involved, it's extremely fast.

        On the other hand, it might be slower than the normal path because it
        adds some overhead to store cache. Moreover when a table is updated,
        pgpool automatically deletes all the caches related to the table. So the
        performance will be degraded by a system with a lot of updates. If the
        cache_hit_ratio is lower than 70%, you might want to disable onl memory
        cache.

    Choosing cache storage:

        You can choose a cache storage: shared memory or memcached (you can't use
        the both).
        Query cache with shared memory is fast and easy because you don't have
        to install and config memcached, but restricted the max size of cache by
        the one of shared memory. Query cache with memcached needs a overhead to
        access network, but you can set the size as you like.

    Restrictions:

      - On memory query cache deletes the all cache of an updated table
        automatically with monitoring if the executed query is UPDATE, INSERT,
        ALTER TABLE and so on. But pgpool-II isn't able to recognize implicit
        updates due to triggers, foreign keys and DROP TABLE CASCADE.
        You can avoid this problem with memqcache_expire by which pgpool deletes
        old cache in a fixed time automatically, or with black_memqcache_table_list
        by which pgpool's memory cache flow ignores the tables.

      - If you want to use multiple instances of pgpool-II with online memory
        cache which uses shared memory, it could happen that one pgpool deletes
        cache, and the other one doesn't do it thus finds old cached result
        when a table gets updated. Memcached is the better cache storage in this
        case.

    New parameters:

      - Add parameters for on memory query cache as follows:
        memory_cache_enabled, memqcache_method, memqcache_expire,
        memqcache_maxcache, memqcache_oiddir. (Tatsuo Ishii)

      - Add parameters about shared memory for on memory query cache as
        follows:
        memqcache_total_size, memqcache_max_num_cache,
        memqcache_cache_block_size. (Tatsuo Ishii)

      - Add parameters about memcached for on memory query cache as follows:
        memqcache_memcached_host, memqcache_memcached_port. (Tatsuo Ishii)

      - Add parameters about relation cache for on memory query cache as
        follows:
        relcache_expire, relcache_size. (Tatsuo Ishii)

      - Add a parameter "check_temp_table" to check if the SELECTed table is
        temp table. (Tatsuo Ishii)

      - Add the parameters of white_memqcache_table_list,
        black_memqcache_table_list that check if the SELECTed tables, temp
        tables and views are to be cached or not. (Nozomi Anzai)

      - Add a parameter "memqcache_auto_cache_invalidation" of the flag if
        query cache is triggered by corresponding DDL/DML/DCL (and
        memqcache_expire). (Yugo Nagata)

    New commands:

      - Add "SHOW pool cache" which shows hit ratio of query cache and the
        status of cache storage.

      - Add "--with-memcached" option to configure. (Nozomi Anzai)

      - Add "-C, --clear-oidmaps" option to "pgpool" command. (Nozomi Anzai)
        If pgpool with memcached starts / restarts with -C option, discard oid
        maps, if not, it can reuse old oid maps and query caches.

  ** Watchdog

    The author is Atsushi Mitani, tested by Yugo Nagata.

    Overview:

        "Watchdog" is a sub process of pgpool-II aiming for adding high
        availability feature to it. Features added by watchdog include:

        - Life checking of pgpool service

          Watchdog monitors responses of pgpool service rather than process. It
          sends queries to PostgreSQL via pgpool which is being monitored by
          watchdog and watchdog checks the response. Also watchdog monitors
          connections to up stream servers (application servers etc.) from the
          pgpool. The connection between the up stream servers and the pgpool is
          monitored as service of pgpool.

        - Mutual monitoring of watchdog processes

          Watchdog processes exchange information on the monitored servers to
          keep the information up to date, and to allow watchdog processes to
          mutually monitor each other.

        - Changing active/standby state in case of certain faults detected

          When a fault is detected in the pgpool service, watchdog notifies the
          other watchdogs of it. Watchdogs decide the new active pgpool if
          previous active pgpool is broken by voting and change active/standby
          state.

        - Automatic virtual IP address assigning synchronous to server switching

          When a standby pgpool server promotes to active, the new active server
          brings up virtual IP interface. Meanwhile, the previous active server
          brings down the virtual IP interface. This enables the active pgpool to
          work using the same IP address even when servers is switched over.

        - Automatic registration of a server as standby in recovery

          When broken server recovers or new server is attached, the watchdog
          process notifies the other watchdog process along with information of
          the new server, and the watchdog process receives information on the
          active server and other servers. Then, the attached server is
          registered as standby.

    New parameters:

        - Add a parameter to enable watchdog: use_watchdog. (Atsushi Mitani)

        - Add the parameters about life checking of pgpool service as follows:
          wd_interval,other_pgpool_port wd_life_point, wd_lifecheck_query,
          other_pgpool_hostname, other_pgpool_port. (Atsushi Mitani)

        - Add the parameters about up to stream connection (e.g. to application
          servers) as follows:
          trusted_servers, ping_path. (Atsushi Mitani)

        - Add the parameters about mutual monitoring of watchdog processes
          as follows:
          wd_hostname, wd_port, other_wd_port. (Atsushi Mitani)

        - Add the parameters about virtual IP as follows:
          ifconfig_path, if_up_cmd, if_down_cmd, arping_path, arping_cmd.
          (Atsushi Mitani)

      __________________________________________________________________

* Enhancements

    - Retry if health check failed rather than immediately do failover. For
      this purpose new directives "health_check_max_retries" and
      "health_check_retry_delay" were added. (Tatsuo Ishii)
      Patch contributed by Matt Solnit.

        Subject: [Pgpool-hackers] Health check retries (patch)
        From: Matt Solnit
        Date: Fri, 18 Nov 2011 16:28:44 -0500

    - Log client IP and port number when pgpool failed to parse given query.
      (Tatsuo)

      This is useful to identify which client gives wrong query without
      enabling log_connections, which produces too many log entries on busy web
      systems.

    - Refactor pool_process_query(). (Tatsuo Ishii)

      Deal with the case when:
        1) query not in progress
        2) other than master node has pending data.
      It is reported that pgpool goes into infinite loop in this case.

        [pgpool-general: 43]
        Re: [Pgpool-general] seemingly hung pgpool process consuming 100% CPU
        http://www.pgpool.net/pipermail/pgpool-general/2011-December/000042.html

    - Add "role" which represents "primary" or "standby" iin streaming
      replication mode for example to "SHOW pool_nodes" command.(Tatsuo Ishii)

    - Add params to the result of "SHOW pool_status": backend_data_directory,
      ssl_ca_cert, ssl_ca_cert_dir, and sort by orders in pgpool.conf. (Anzai)

    - Commentout params about system db from pgpool.conf.sample-*. (Nozomi Anzai)

    - Add new parameter to failover/failback/followmaster command. (Tatsuo Ishii)

        %r: new master port number
        %R: new master database cluster path

    - Allow to reload to recognize md5 password change. (Tatsuo Ishii)
      Before, the only way to recognize md5 password change was restarting
      pgpool-II. Patch contributed by Gurjeet Singh.

    - Remove unused parameter "query" from is_set_transaction_serializable().
      (Tatsuo Ishii)

    - Fix on memory query cache section's comments in pgpool.com in the way
      which other sections employ. (Tatsuo Ishii)

    - Add missing health_check_max_retries and health_check_retry_delay
      directives to pgpool.conf.sample-master-slave, pgpool.conf.sample-replication
      pgpool.conf.sample-stream. (Tatsuo Ishii)

    - Fix pool_ssl_write. It seems someone forgot to do retrying when SSL
      returns SSL_ERROR_WANT_READ or SSL_ERROR_WANT_WRITE.
      Per [pgpool-general: 797]

      [pgpool-general: 797]
      Re: Problem with pgpool when using SSL, for client/pgpool communication
      http://www.sraoss.jp/pipermail/pgpool-general/2012-July/000807.html

    - Improve the design of manuals. (Nozomi Anzai)

      __________________________________________________________________

* Bug Fix

    - Fix memory leak in Raw mode.(Tatsuo Ishii)

    - Fix failover/failback in Raw mode. (Tatsuo Ishii)
      - Simply does not failover if target node is not master.
      - Fail to select master node if the node is in CON_UP.

    - Allow health check retry while connect(). (Tatsuo Ishii)

      It is reported that connect() blocks sigalarm under some conditions, for
      example: When system is configured for security reasons not to return
      destination host unreachable messages ([pgpool-general: 131])
      Part of changes are contributed by Stevo Slavic.

      [pgpool-general: 131] Healthcheck timeout not always respected
      http://www.pgpool.net/pipermail/pgpool-general/2012-January/000131.html

    - Fix pool_send_and_wait() to send or not to send COMMIT / ABORT depending
      on the transaction state on each node. (Tatsuo Ishii)

      It is possible that only primary is in an explicit transaction but
      standby is not in it if multi statement query has been sent.
      Per bug report [pgpool-general-jp: 1049].

    - Fix load balance in Solaris. (Tatsuo Ishii)

      Problem is, random() in using random() in Solaris results in strange
      load balancing calculation.
      Use srand()/rand() instead although they produce lesser quality random
      Problem reported at [pgpool-general: 396].

      [pgpool-general: 396] strange load balancing issue in Solaris
      http://www.pgpool.net/pipermail/pgpool-general/2012-April/000397.html

    - Fix segfault of pcp_systemdb_info not in parallel mode. (Nozomi Anzai)

    - Fix "unnamed prepared statement does not exist" error. (Tatsuo Ishii)

      This is caused by pgpool's internal query, which breaks client's unnamed
      statements. To fix this, if extended query is used, named
      statement/portal for internal are used for internal query.

    - Fix hangup when query conflict occurs in Hot-Standby mode. (Yugo Nagata)
      Query example to reproduce:

          (S1) BEGIN;
          (S1) SELECT * FROM t;
          (S2) DELETE FROM t;
          (S2) VACUUM t;

    - Fix pool_process_query() bug reported in [pgpool-general: 672].
      (Tatsuo Ishii)

      This is caused by the function waits for primary node which does not
      have pending data, while standbys have pending data.

      [pgpool-general: 672] Transaction never finishes
      http://www.pgpool.net/pipermail/pgpool-general/2012-June/000676.html

    - Fix wait_for_query_response() not to send param status to frontend if
      frontend is NULL. (Tatsuo Ishii)

      This could happen while processing reset_query_list and occur crash.

    - Fix bug with treatment of BEGIN TRANSACTION in master/slave mode.
      (Tatsuo Ishii)

      Original complain is [pgpool-general: 714].
      From 3.1, pgpool-II sends BEGIN.. to all DB nodes. Of course we cannot
      send BEGIN TRANSACTION READ WRITE to standby nodes.
      Problem is, we did not check BEGIN WORK ISOLATION LEVEL SERIALIZABLE;
      and sent to standby nodes. Of course this is wrong, since it's not
      allowed to run transactions in serializable mode on standby nodes.
      So added check for BEGIN WORK ISOLATION LEVEL SERIALIZABLE case.

      [pgpool-general: 714]
      Load Balancing / Streaming Replication / Isolation Level serializable
      http://www.pgpool.net/pipermail/pgpool-general/2012-July/000719.html

    - Fix send_to_where() to send the query to only primary if the it is like
      SET TRANSACTION ISOLATION LEVELSERIALIZABLE etc. (Tatsuo Ishii)

      Case in streaming replication mode. Previously, it was sent to not only
      primary but also to standby and of course this causes an error.
      Similar SQLs are:
       SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL SERIALIZABLE or
       SET transaction_isolation TO 'serializable'
       SET default_transaction_isolation TO 'serializable'

      Original complain is [pgpool-general: 715].

      [pgpool-general: 715]
      Re: Load Balancing / Streaming Replication / Isolation Level serializable
      http://www.pgpool.net/pipermail/pgpool-general/2012-July/000720.html

    - Prevent errors even if memcached is not available with on memory query
      cache enabled and cache storage is memcached. (Tatsuo Ishii)

      This is mainly achieved by modifying pool_fetch_cache to pretend
      "cache not found" if memcached_get returns error other than
      MEMCACHED_NOTFOUND. Also we set pool_config->memory_cache_enabled to 0 to
      prevent future errors by accessing memcached.

    - Run rerun libtoolize with --copy and --force option. (Tatsuo Ishii)

      This should prevent build problems in different environment.
      Following commands were executed:
      libtoolize --copy --force
      aclocal
      autoheader
      automake -a
      autoconf

    - Fix pool_ssl_read. (Tatsuo Ishii)

      When SSL_read returns unknown error, treat as if EOF detected and returns 0
      to caller (pool_read). This is same as libpq's behavior. Also this will
      avoid unwanted failover in pool_read. pool_read triggers failover if
      underlying I/O functions, read(2) or pool_ssl_read returns -1.

    - Fix pool_process_query. (Tatsuo Ishii)

      When other than primary sends packet, pgpool tries to terminate session
      gracefully and hung because now ssl_read returns EOF, rather than error
      and triggers failover. For example [pgpool-general: 766] reported this:

      2012-07-17 00:11:03 NZST [15692]: [257-1] ERROR: canceling statement
      due to conflict with recovery
      2012-07-17 00:11:03 NZST [15692]: [258-1] DETAIL: User query might
      have needed to see row versions that must be removed.
      2012-07-17 00:11:03 NZST [15692]: [259-1] STATEMENT: <SNIP>
      2012-07-17 00:11:03 NZST [15696]: [366-1] FATAL: terminating
      connection due to conflict with recovery
      2012-07-17 00:11:03 NZST [15696]: [367-1] DETAIL: User query might
      have needed to see row versions that must be removed.

      In this case pool_process_query should return POOL_ERROR, rather than
      POOL_END.

      [pgpool-general: 766]
      Re: pgpool dropping backends too much
      http://www.pgpool.net/pipermail/pgpool-general/2012-July/000774.html

    - If frontend terminates while reading large number of query results
      from backend, pgpool continues to read from backend and write to
      frontend until all query results consumed. (Tatsuo Ishii)

      This will take very long time if query results is huge. To finish pgpool
      session as soon as possible, modify pool_flush_it to returns error if
      fail to write to frontend when operated in other than replication mode.
      In replication mode, we need to keep the previous behavior to save
      consistency among backends).

      Also fix SimpleForwardToFrontend to return pool_write_and_flush error
      status. Before it was ignored.


===============================================================================
3.1 Series (2011/09/08 - )
===============================================================================

                        3.1.20 (hatsuiboshi) 2016/08/31

* Version 3.1.20

    This is a bugfix release against pgpool-II 3.1.19.

    __________________________________________________________________

* Bug fixes

    - Fix buffer over run problem in "show pool_nodes". (Tatsuo Ishii)

      While processing "show pool_nodes", the buffer for hostname was too
      short. It should be same size as the buffer used for pgpool.conf.
      Problem reported by a twitter user who is using pgpool on AWS (which
      could have very long hostname).

    - Fix usage of wait(2) in pgpool main process. (Tatsuo Ishii)

      The usage of wait(2) in pgpool main could cause infinite wait in the
      system call. Solution is, to use waitpid(2) instead of wait(2).

    - Fix "kind mismatch" error message in pgpool. (Muhammad Usama)

      Many of "kind mismatch..." errors are caused by notice/warning
      messages produced by one or more of the DB nodes. In this case now
      Pgpool-II forwards the messages to frontend, rather than throwing the
      "kind mismatch..." error. This would reduce the chance of "kind
      mismatch..."  errors.

      See [pgpool-hackers: 1501] for more details.

    - Replace "MAJOR" macro to prevent occasional failure. (Tatsuo Ishii)

      The macro calls pool_virtual_master_db_node_id() and then access
      backend->slots[id]->con using the node id returned.  In rare cases, it
      could point to 0 (in case when the DB node is not connected), which
      gives access to con->major, then it causes a segfault.

      See bug 225 for related info.

    - doc : fix Japanese document typo. (Bo Peng)

    - Fixing a typo in the log message. (Muhammad Usama)

    - doc : Add comment to the document about connection_cache. (Tatsuo Ishii)

===============================================================================

                        3.1.19 (hatsuiboshi) 2016/06/17

* Version 3.1.19

    This is a bugfix release against pgpool-II 3.1.18.

    __________________________________________________________________

* Bug fixes

    - Fix is_set_transaction_serializable() when
      SET default_transaction_isolation TO 'serializable'. (Bo Peng)

      SET default_transaction_isolation TO 'serializable' is sent to
      not only primary but also to standby server in streaming replication mode,
      and this causes an error. Fix is, in streaming replication mode,
      SET default_transaction_isolation TO 'serializable' is sent only to the
      primary server.

      See bug 191 for related info.

    - Fix Chinese documentation bug about raw mode (Yugo Nagata, Bo Peng)
      Connection pool is available in raw mode.

    - Fix confusing comments in pgpool.conf (Tatsuo Ishii)

    - Permit pgpool to support multiple SSL cipher protocols (Muhammad Usama)

      Currently TLSv1_method() is used to initialize the SSL context, that puts an
      unnecessary limitation to allow only TLSv1 protocol for SSL communication.
      While postgreSQL supports other ciphers protocols as well. The commit changes
      the above and initializes the SSLSession using the SSLv23_method()
      (same is also used by PostgreSQL). Because it can negotiate the use of the
      highest mutually supported protocol version and remove the limitation of one
      specific protocol version.

    - If statement timeout is enabled on backend and do_query() sends a (Tatsuo Ishii)
      query to primary node, and all of following user queries are sent to
      standby, it is possible that the next command, for example END, could
      cause a statement timeout error on the primary, and a kind mismatch
      error on pgpool-II is raised.

      This fix tries to mitigate the problem by sending sync message instead
      of flush message in do_query(), expecting that the sync message reset
      the statement timeout timer if we are in an explicit transaction. We
      cannot use this technique for implicit transaction case, because the
      sync message removes the unnamed portal if there's any.

      Plus, pg_stat_statement will no longer show the query issued by
      do_query() as "running".

      See bug 194 for related info.

    - Deal with the case when the primary is not node 0 in streaming replication mode. (Tatsuo Ishii)

      http://www.pgpool.net/mantisbt/view.php?id=194#c837 reported that if
      primary is not node 0, then statement timeout could occur even after
      bug194-3.3.diff was applied. After some investigation, it appeared
      that MASTER macro could return other than primary or load balance
      node, which was not supposed to happen, thus do_query() sends queries
      to wrong node (this is not clear from the report but I confirmed it in
      my investigation).

      pool_virtual_master_db_node_id(), which is called in MASTER macro
      returns query_context->virtual_master_node_id if query context
      exists. This could return wrong node if the variable has not been set
      yet. To fix this, the function is modified: if the variable is not
      either load balance node or primary node, the primary node id is
      returned.

    - change the Makefile under the directory src/sql/, that is proposed (Bo Peng)
      by [pgpool-hackers: 1611]

    - Fix a possible hang during health checking (Yugo Nagata)

      Health checking was hang when any data wasn't sent
      from backend after connect(2) succeeded. To fix this,
      pool_check_fd() returns 1 when select(2) exits with
      EINTR due to SIGALRM while health checking is performed.

      Reported and patch provided by harukat and some modification
      by Yugo. Per bug #204.

      backported from 3.4 or later;
      https://git.postgresql.org/gitweb/?p=pgpool2.git;a=commitdiff;h=ed9f2900f1b611f5cfd52e8f758c3616861e60c0

    - Fix bug with load balance node id info on shmem (Tatsuo Ishii)

      There are few places where the load balance node was mistakenly put on
      wrong place. It should be placed on: ConnectionInfo *con_info[child
      id, connection pool_id, backend id].load_balancing_node].  In fact it
      was placed on: *con_info[child id, connection pool_id,
      0].load_balancing_node].

      As long as the backend id in question is 0, it is ok. However while
      testing pgpool-II 3.6's enhancement regarding failover, if primary
      node is 1 (which is the load balance node) and standby is 0, a client
      connecting to node 1 is disconnected when failover happens on node
      0. This is unexpected and the bug was revealed.

      It seems the bug was there since long time ago but it had not found
      until today by the reason above.

===============================================================================

                        3.1.18 (hatsuiboshi) 2016/04/26

* Version 3.1.18

    This is a bugfix release against pgpool-II 3.1.17.

    __________________________________________________________________

* Bug fixes

    - Removing the limit on the maximum number of items in the
      black_function_list and white_function_list lists. (Muhammad Usama)

      extract_string_tokens in pool_config uses the fixed size malloc on
      the array to hold the black_function_list/white_function_list items.
      This imposes a limit of maximum items in these lists.
      The fix is to use realloc to increase the array size when it gets full.

    - Redirect all user queries to primary server (Tatsuo Ishii)

      Up to now some user queries are sent to other than the primary server
      even if load_balance_mode = off. This commit changes the behavior: if
      load_balance_mode = off in streaming replication mode, now all the
      user queries are sent to the primary server only.

      Per bug #189.

    - Change the PID length of pcp_proc_count command result to 6 characters
      long (Bo Peng)

      If the pgpool process ID are over 5 characters, the 6th character of each
      process ID will be removed. This commit changes the process ID length of
      pcp_proc_count command result to 6 characters long.

      Per bug #188.

===============================================================================

                        3.1.17 (hatsuiboshi) 2016/04/04

* Version 3.1.17

    This is a bugfix release against pgpool-II 3.1.16.

    __________________________________________________________________

* Bug fixes

    - doc: Change description of backend_flag (Tatsuo Ishii)

      It is pointed out that restarting pgpool-II is not necessary.

      Per [pgpool-general-jp: 1394].

    - doc: Fix installation procedure. (Tatsuo Ishii)

      With PostgreSQL 9.4 or later, installing pgpool_regclass is not needed.

    - Fix to validate the PCP packet length (Muhammad Usama)

      Without the validation check, a malformed PCP packet can crash the
      PCP child and/or can run the server out of memory by sending the packet
      with a very large data size.

    - Fix a reset query stuck problem (Muhammad Usama)

      The solution is to return  POOL_END_WITH_FRONTEND_ERROR instead of
      POOL_END when pool_flush on front-end socket fails.

      The original report is
      [pgpool-general: 4265] Pgpool - connection hangs in DISCARD ALL

===============================================================================

                        3.1.16 (hatsuiboshi) 2016/02/05

* Version 3.1.16

    This is a bugfix release against pgpool-II 3.1.15.

    __________________________________________________________________

* Bug fixes

    - doc: Fix misinformation regarding load balancing in docs (Tatsuo Ishii)

      In streaming replication mode, DECLARE, FETCH, CLOSE and SHOW are sent
      to primary node only. Pointed out in [pgpool-general-jp: 1378].

    - Issue fsync() when writing pgpool_status (Tatsuo Ishii)

      This ensures that pgpool_status is saved to permanent storage and
      allow to survive after system crash.

    - doc: Fix wrong description about log_standby_delay in the document
      (Yugo Nagata)

    - Fix bug with "SET TRANSACTION READ ONLY" (Tatsuo Ishii)

      Pgpool-II remembers that non read only queries (including SET) were
      executed in an explicit transaction and adds a "writing transaction"
      mark to the transaction. The mark affects the query routing behavior
      of pgpool-II while running in streaming replication mode. Pgpool-II
      starts sending queries to the primary after the mark is set. Because
      the effect of writing queries may appear on standbys after some delay
      in streaming replication mode, it is safer to route read queries to
      the primary after the mark is set.

      However there's oversight here. "SET TRANSACTION READ ONLY" does no
      data modification and should be treated as an exception.

      Per bug #157.

    - Fix FATAL error with reloading (Tatsuo Ishii)

      While reloading pgpool.conf, the number of DB nodes is tentatively set
      to 0, then counted up until reaching to the actual number of backends
      by the pgpool main process. Unfortunately the variable was on the
      shared memory and it confused pgpool child process when they were using
      the variable and this caused FATAL error.

      Per bug #156 report by harukat.

    - Ignore close statement/portal request if they do not exist (Tatsuo Ishii)

      In this case just returns a close complete message to client.
      This is a back port of the following commit from pgpool-II 3.4:

      1a37e1c35bd8b6f10f524693bbcb7b51f73b4bf0

===============================================================================

                        3.1.15 (hatsuiboshi) 2015/07/24

* Version 3.1.15

    This is a bugfix release against pgpool-II 3.1.14.

    __________________________________________________________________

* Bug fixes

    - Fix "cannot find xlog functions" error in pgpool-recovery
      (Muhammad Usama)

      The argument data type of PostgreSQL's pg_xlogfile_name() function
      has been changed from text to pg_lsn since PostgreSQL 9.4. And
      pgpool-recovery was still trying to locate the function by old
      signature.

    - Do not send a query for checking insert lock in non replication mode
      with extended query (Tatsuo Ishii)

===============================================================================

                        3.1.14 (hatsuiboshi) 2015/04/08

* Version 3.1.14

    This is a bugfix release against pgpool-II 3.1.13.

    __________________________________________________________________

* Bug fixes

    - Enlarge POOLCONFIG_MAXDESCLEN to 80 (Tatsuo Ishii)

      This is used in show pool_status command and limits the length of
      parameter description.  Unfortunately recovery_timeout description is
      64 chars, which is 1 byte longer than former definition of the macro.

    - Support SSL certificate chains in the certificate file for incoming
      frontend connections (Muhammad Usama)

    - Fix a problem with pcp_detach_node about graceful node detach (Muhammad Usama)

      When graceful node detach is requested gracefully, pcp_detach_node should
      check if it is allowed to process detach_node command on the particular
      node before blocking the incoming connections and closing the existing
      connections.

===============================================================================

                        3.1.13 (hatsuiboshi) 2015/02/05

* Version 3.1.13

    This is a bugfix release against pgpool-II 3.1.12.

    __________________________________________________________________

* Bug fixes

    - doc: Describe explicitly that the number of slave nodes is not
      necessarily 1 (Tatsuo Ishii)

    - Fix uninitialized variable (Tatsuo Ishii)

      Per Coverity 1234603.

    - doc: Fix missing release note entries in the previous release
      (Tatsuo Ishii)

    - Fix node id range check bug in trigger_failover_command(). (Tatsuo Ishii)

      The node id should be lower than NUM_BACKENDS. Probably harmless since
      callers never pass node ids greater or equal to NUM_BACKENDS.

    - Fix to disable debug mode by reloading config (Yugo Nagata)

      Per bug #114
      http://www.pgpool.net/mantisbt/view.php?id=114

===============================================================================

                        3.1.12 (hatsuiboshi) 2014/09/05

* Version 3.1.12

    This is a bugfix release against pgpool-II 3.1.11.

    __________________________________________________________________

* Bug fixes

    - Fix a typo of pgpool.spec (Yugo Nagata)

    - Fix bug that worker child process keeps failing when there's no
      primary backend (Tatsuo Ishii)

      Problem identified and fix contributed by Junegunn Choi.

      See [pgpool-hackers: 471] for more details.

    - Close listen socket when smart shutdown request is made (Tatsuo Ishii)

      When smart shutdown process starts, pgpool children still listen on
      the port and clients can send further connection requests which fail
      in the end. Which is not only waste of time, but also prevents a load
      balancer which sits in front of pgpool from realizing the pgpool is
      going down.

      Problem analyzed and patch provided by Junegunn Choi in [pgpool-hackers
      474], and enhanced to take care not only inet domain socket but UNIX
      domain socket by Tatsuo Ishii.

    - doc: Add cautions that recovery commands are killed by statement_timeout
      of PostgreSQL. (Tatsuo Ishii)

    - doc: Remove old restriction description which is no longer true
      (Tatsuo Ishii)

    - Fix return type of text_to_lsn() function (Yugo Nagata)

      This caused compile warning.

    - Fix file descriptor leak when daemonize. (Tatsuo Ishii)

      Per Coverity 1111471.

    - Fix memory leak. (Tatsuo Ishii)

      Per Coverity 1111442.

    - Fix pgpool.init's long-standing bug of stop/restart failure
      (Yugo Nagata)

      In previous, pgpool.init uses killproc for stopping pgpool, but there
      are several problems. In the new version, "pgpool -m fast stop" is
      used in stop command.

      Original patch contributed by Ryan DeShone and modified by Yugo Nagata.

      See [pgpool-hackers: 239][pgpool-hackers: 512].

    - Disable statement_timeout of PostgreSQL while executing online recovery
      (Tatsuo Ishii)

      Online recovery may take very long time and user may enable statement
      timeout. To prevent online recovery canceled by statement timeout,
      disable statement timeout in the connection used by online recovery.

      See [pgpool-general: 2919] for more details.

    - Remove unnecessary call to pool_shmem_exit() which removes semaphore
      when it shouldn't (Tatsuo Ishii)

      exit_handler checks if the process is parent or not. This is
      good. However, even if it is a child process, it calls
      pool_shmem_exit() which removes semaphore and shmem when it should
      not. It should be called only from parent process.

      Per bug #102.
      http://www.pgpool.net/mantisbt/view.php?id=102

    - Fix reset query stuck problem. (Tatsuo Ishii)

      It is reported that reset query (DISCARD ALL etc.) occasionally does
      not finish and pgpool child remain waiting for reply from backend thus
      client cannot connect to pgpool.

      The cause of problem is not identified yet but if client suddenly
      closes connection to pgpool in the middle of query processing, backend
      may not accept the reset queries because they are not ready for query.

      The fix is, if frontend closes connection in unexpected way, query
      process loop immediately returns with new state:
      POOL_END_WITH_FRONTEND_ERROR and pgpool closes connection to
      PostgreSQL then goes back to new connection request waiting loop.

      Also, pgpool closes connections to backend when client_idle_limit is
      set and the idle limit.

      Per bug #107.
      http://www.pgpool.net/mantisbt/view.php?id=107

===============================================================================

                        3.1.11 (hatsuiboshi) 2014/03/24

* Version 3.1.11

    This is a bugfix release against pgpool-II 3.1.10.

    __________________________________________________________________

* Bug fixes

    - doc: Add mention about "listen queue" and how to increase the "backlog"
      in the num_init_children section. (Tatsuo Ishii)

    - Fix bad performance of unlogged tables detection code. (Tatsuo Ishii)

      Pointed out at [pgpool-hackers: 435][[pgpool-general:2325].

    - Fix primary node detection logic. (Tatsuo Ishii)

      There's a possibility that primary node is not detected. This happens
      in following situation.  node 0: primary, node 1: standby. Node 0 goes
      down. Health checking detects the fact but local status is not updated
      yet. Primary node finding (find_primary_node) runs. Node 0's status is
      yet healthy. Because find_primary_node fails to connect to node 0, it
      immediately returns -1 and fails to find that fact that node 1 is now
      primary.

      Fix is just continuing to look for primary node when fails to connect
      to a node.

      Per [pgpool-general: 2409].

    - Fix jdbc DML fails when operated in raw mode and auto commit is off.
      (Tatsuo Ishii)

      This is reported in bug #92.

    - Avoid to send queries to unrelated nodes in streaming replication mode.
      (Tatsuo Ishii)

      Pgpool-II sends certain queries, such as BEGIN, END and SET commands to
      all of DB nodes. However in streaming replication mode, only primary
      node and at most one standby node are only concerned (if primacy node
      is selected as the load balance node, only 1 node is concerned).

      See [pgpool-hackers: 464] for more details.

    - Fix possible buffer overrun problem and memory leak. (Tatsuo Ishii)

      Per Coverity 1111465 and 1111482.

    - Fix possible buffer overrun. (Tatsuo Ishii)

      Replace strcpy() with strlcpy(). Per Coverity report 1111478, 1111480,
      1111481.

    - Fix freeing NULL. (Tatsuo Ishii)

      Per Coverity 1111384.

    - Fix memory leak. (Tatsuo Ishii)

      Per Coverity 1111446.

    - Fix a segmentation fault in parallel mode with system_db_hostname is
      empty (Yugo Nagata)

    - Fix to output debug messages in processing pgpool.conf with -d option
      (Yugo Nagata)

      Previously, some debug messages in pool_get_config() ware not output
      even when -d option was used.

    - Fix JDBC exception of prepared statement including now() in
      replication mode (Yugo Nagata)

      With JDBC, when a prepared statement is executed more than
      PrepareThreshold times, the statement is named and Describe message
      is sent after Parse. With named statement, pgpool rewrite now() to
      parameter in replication mode. Hence, rewritten query has additional
      parameter than original. In this case, ParameterDescription message
      sent to frontend (response of Describe) should include OIDs of the
      same number os original query's parameters. Otherwize, JDBC throws
      ArrayIndexoutOfBoundsException.

      This is reported in [pgpool-general-jp: 1192].

    - Fix backend error of prepared statement about table which has column whose
      default value is now() in replication mode (Yugo Nagata)

      When pgpool parses a named prepared statement with default now(),
      timestamps are replaced to additional parameters. So, Bind message also
      should included additional parameter format codes. However, when the
      number of original parameter was one, pgpool didn't handle this. This
      caused a error like "incorrect binary data format in bind parameter 2".

    - doc: Add description about parallel mode doesn't support PREPARE (Yugo Nagata)

      Per bug #93

===============================================================================

                        3.1.10 (hatsuiboshi) 2013/12/06

* Version 3.1.10

      This is a bugfix release against pgpool-II 3.1.9.

    __________________________________________________________________

* Bug fixes

    - Fix incorrect time stamp rewriting in replication mode for certain time
      zones. (Tatsuo Ishii)

      Time stamp rewriting calls "SELECT now()" to get current time.
      Unfortunately the buffer for the current time is too small for certain
      time zones such as "02:30". Note that non-30-minutes-time-zone such as
      "0900" does not reveal the problem. This explains why we haven't the bug
      report until today.

      Bug reported in [pgpool-general: 2113] and fix provided by Sean Hogan.
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002142.html

    - Makefile: Replace pg_config by $(PG_CONFIG) in Makefiles so it can be
      overridden at build time when compiling for different PG major versions.
      (Tatsuo Ishii)

      Patch contributed by Christoph Berg ([pgpool-general: 2127]).
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002156.html

    - configure: Remove -lcompat because it confuses FreeBSD per bug#15.
      (Tatsuo Ishii)
      http://www.pgpool.net/mantisbt/view.php?id=15

    - Fix segfault when pgpool.conf does not set log_standby_delay.
      (Tatsuo Ishii)

      This is caused by wrong initialization for log_standby_delay in
      pool_config.l.
      Per bug#74. http://www.pgpool.net/mantisbt/view.php?id=74

    - doc: Modify descriptions about restrictions of parallel mode
      Multiple rows INSERT using VALUES are not supported in parallel mode.
      (Yugo Nagata)

    - Avoid calling find_primary_node_repeatedly() when standby node goes
      down. (Tatsuo Ishii)

      This will reduce the time to failover. Per bug #75, patch modified by
      Tatsuo Ishii. http://www.pgpool.net/mantisbt/view.php?id=75

    - Fix data inconsistency problem with native replication mode + extended
      protocol case. (Tatsuo Ishii)

      It is reported that concurrent INSERT using JDBC driver causes data
      difference among database node. This only happens following conditions
      are all met:

      1) Native replication mode
      2) Extended protocol used
      3) The portal created by parse message is reused by bind message
      4) autocommit is on
      5) SERIAL (sequence) is used

      Pgpool-II's parse message function knows it has to lock the target
      table when INSERT (plus #5) is issued by clients. Unfortunately bind
      message function did not know it. Once parse/bind/execute finishes,
      pgpool releases the lock obtained by parse because of #4. JDBC wants
      to reuse the portal and starts the cycle from bind message, which does
      not obtain lock. As as result, lock-free INSERT are floating around
      which causes data inconsistency of course.  The solution is, lock the
      table in bind phase.

      For this bind needs to issue LOCK in extended protocol. This was a little
      bit hard because the module (do_command()) to issue internal SQL command
      (other than SELECT) does not support extended protocol.
      To solve the problem do_query() is modified so that it accepts other than
      SELECT because it already accepts extended protocol.
      The modification is minimum and is only tested for the case called from
      insert_lock(). I do not recommend to replace every occurrence of
      do_command () with do_query() at this point.

      BTW the reason why the bug is not reported is, most users uses JDBC
      with auto commit = off. In this case, the lock obtained by parse persists
      until user explicitly issues commit or rollback.

      Per bug report by Steve Kuekes in [pgpool-general: 2142].
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002171.html

    - Fix error message in read_password_packet(). (Tatsuo Ishii)

    - Fix memory leak when do_query() fails in timestamp rewriting.
      (Tatsuo Ishii)

      For this purpose free_select_result() is changed to accept NULL argument.
      Per Coverity report "1111454, 1111455 Resource leak".

    - Fix target node selection logic when "DEALLOCATE portal|statement".
      (Tatsuo Ishii)

      When "DEALLOCATE portal|statement" is used and last prepared statement or
      portal was not found, target node selection map is not set. Probably this
      is not actually harmful because prepared statement or portal was not found
      is an error case. The bug was there since day 0.

      Per Coverity report "1111491 Structurally dead code".

    - Fix range check bug of MAX_NUM_BACKENDS in corner case. (Tatsuo Ishii)

      MAX_NUM_BACKENDS is the allowed max number of DB nodes (128, at this
      point). In reality, probably no one ever tried more than 128 DB nodes
      and that's the reason why nobody noticed.

      Per Coverity report "1111429, 1111430 and 1111431 Out-of-bounds write".

    - Fix that the script forgets to allow public access to pgpool_catalog.
      (Tatsuo Ishii)

      The bug prevents inserting data into user tables if pgpool_catalog is
      created in native replication mode.  The bug was there from day 1. I
      wonder why nobody noticed until today.
      Per [pgpool-general-jp: 1229].
      http://www.sraoss.jp/pipermail/pgpool-general-jp/2013-November/001228.html

    - Fix uninitialized variable in error case in pool_do_auth().
      (Tatsuo Ishii)

      If there's no valid backend, pgpool will return garbage pid to frontend in
      auth phase. Actually because no backend is available, frontend will be
      disconnected later on. So this is not harmless.
      Per Coverity report "1127331 Uninitialized scalar variable".

    - Fix to add node id range check when issue an error message using node
      id. (Tatsuo Ishii)
      Per Coverity report #1111433 "Out-of-bounds read".

    - Fix buffer overrun bug and resource leak bug of parse_copy_data().
      (Tatsuo Ishii)
      Per Coverity report 1111427 "Out-of-bounds write" and 1111453 "Resource
      leak".

    - Fix possible segfault in CopyDataRaws(). (Tatsuo Ishii)
      Coverity pointed out that if pool_get_id() returns an error, VALID_BACKEND
      will access out of array.
      Per Coverity report 1111413 "Memory - illegal accesses".

    - Fix resource leak in make_persistent_db_connection. (Tatsuo Ishii)

      For this purpose, new static function free_persisten_db_connection_memory
      is added.
      Per Coverity report #1111468.

===============================================================================

                        3.1.9 (hatsuiboshi) 2013/09/06

* Version 3.1.9

      This is a bugfix release against pgpool-II 3.1.8.

    __________________________________________________________________

* Bug fixes

    - Fix a mistake in ssh command of doc/basebackup.sh (Tatsuo Ishii)

    - Fix a bug in parsing prepared statements with transaction handling in
      replication mode (Tatsuo Ishii)

      Parse() automatically starts a transaction for non SELECT query to keep
      consistency among nodes in replication mode. But this wasn't closed. If
      wrong query comes in, the transaction goes into an abort state but pgpool
      does not close the transaction. Thus next query causes error because the
      transaction is still in abort status.

      This problem was reported in [pgpool-general: 1877] by Sean Hogan.

      [pgpool-general: 1877] current transaction is aborted, commands ignored
      http://www.sraoss.jp/pipermail/pgpool-general/2013-July/001905.html

    - Fix typos of the japanese document (Yugo Nagata)

===============================================================================

                        3.1.8 (hatsuiboshi) 2013/07/10

* Version 3.1.8

      This is a bugfix release against pgpool-II 3.1.7.

    __________________________________________________________________

* Bug fixes

    - Add mention about "-D" option to the man page. (Tatsuo Ishii)

    - Consider timeout waiting for completion of failback request in on line
      recovery (Tatsuo Ishii)

      This will prevent the situation that recovery operation continues forever
      and we cannot even shutdown pgpool-II main process. This could happen
      especially while executing follow master command.

    - Fix a bug that %H of follow_master_command is not assigned correctly the
      new primary node in stream replication mode
      (Tatsuo Ishii)

    - Fix do_query() to not hang when PostgreSQL returns an error
      (Tatsuo Ishii)

      The typical symptom is "I see SELECT is keep on running according to
      pg_stat_activity". To fix this pgpool-II just exits the process and
      kill the existing connection.  This is not gentle but at this point I
      believe this is the best solution.

    - Fix bug with do_query which causes hung in extended protocol
      (Tatsuo Ishii)

      This problem could occur when insert lock is enabled and
      pgpool_catalog.insert_lock exists, See [pgpool-general: 1684] for more
      details.

      [pgpool-general: 1684] insert_lock hangs
      http://www.sraoss.jp/pipermail/pgpool-general/2013-May/001711.html

    - Fix unnecessary degeneration caused by error on commit (Tatsuo Ishii)

      In master slave mode, if master gets an error at commit, while other
      slaves are normal at commit, we don't need to degenerate any backend
      because it is likely that the "kind mismatch error" was caused by a
      deferred trigger.

    - Fix to register pgpool_regclass in pg_catalog schema (Tatsuo Ishii)

      This is necessary to deal with clients which restricts schema search path
      to pg_catalog only. Postgres_fdw is such a client.

    - Fix a potential crash in pg_md5 command (Muhammad Usama)

    - Fix a segmentation fault of a child process that occurs when a startup
      packet has no PostgreSQL user information (Yugo Nagata)

      You can reproduce it by

          $ psql -p 9999 -U ''

      If enable_pool_hba is on, a child process terminates by segmentation
      fault. Otherwise if enable_pool_hba is off, the error message is

          ERROR: pool_discard_cp: cannot get connection pool for user (null)
                 database (null)

      In both cases, psql terminates with no message on frontend.

      In the fixed version, if PostgreSQL user is not specified in startup packet,
      the message as following is output to both log and frontend. This is
      the same behavior as PostgreSQL.

          FATAL: no PostgreSQL user name specified in startup packet

    - Move ssl_ca_cert and ssl_ca_cert_dir descriptions to the SSL section
      (Yugo Nagata)

    - Add ssl_ca_cert and ssl_ca_cert_dir descriptions to the japanese document
      (Yugo Nagata)

    - Fix to verify the backend node number in pcp_recovery_node (Yugo Nagata)

      When an invalid number is used, null value is passed as an arguments
      of recovery script, and this causes a malfunction. In especially,
      rsync may delete unrelated files in basebackup scripts.

===============================================================================

                        3.1.7 (hatsuiboshi) 2013/4/26

* Version 3.1.7

      This is a bugfix release against pgpool-II 3.1.6

    __________________________________________________________________

* Bug fixes

    - Fix to show pool_passwd in "SHOW pool_status". (Yugo Nagata)

    - Fix long standing bug with timestamp rewriting code for processing
      extended protocol. (Tatsuo Ishii)

      Parse() allocate memory using palloc() while rewriting the parse
      message.  Problem is, the rewritten message was kept in the data which
      is managed by pool_create_sent_message() etc. The function assumes
      that all the data is in session context memory. However, palloc()
      allocates memory in query context of course, and gets freed later on
      when the query context disappears. And the function tries to free the
      memory as well, which causes various problems, including segfault and
      double free. To fix this, memory to store rewritten message is
      allocated using session context. The bug was there since pgpool-II 3.0
      was born.

      Problem analysis and patch contributed by Naoya Anzai.

      [pgpoolgenera-jp: 1146]. (in Japanese)
      http://www.pgpool.net/pipermail/pgpool-general-jp/2013-March/001145.html

    - Fix bug with md5 auth long user name handling. (Tatsuo Ishii)

      If user name is longer than 32 bytes, md5 authentication doesn't work.
      Problem reported in [pgpool-general: 1526] by Thomas Martin.

      [pgpool-general: 1526]
      [pgPool-II 3.2.3] MD5 authentication and username longer than 32 characters.
      http://www.pgpool.net/pipermail/pgpool-general/2013-March/001551.html

    - Fix to calculate replication delay only if standby server is behind from
      the primary server. (Yugo Nagata)

      When the primary server is behind from standby server, negative value of
      delay is calculated and the value is assigned to unsigned variable. It
      causes a log message informing negative replication delay. And what is
      worse, it also causes SELECT queries to be sent to the primary in load
      balance even though there are no replication delay in fact.

      The problem is reported and analyzed by Saitoh Hidenori in
      [pgpool-genera-jp: 1145].

      [pgpool-general-jp: 1145] (in Japanese)
      http://www.pgpool.net/pipermail/pgpool-general-jp/2013-March/001144.html

    - pgpool-recovery adopts PostgreSQL 9.3. (Tatsuo Ishii)

      Patch contributed by Asif Rehman. Slight editing by Tatsuo Ishii.

      [pgpool-hackers: 180]
      compile error in ppool-recovery
      http://www.pgpool.net/pipermail/pgpool-hackers/2013-April/000179.html

    - Fix pool_has_pgpool_regclass() to check execute privilege of
      pgpool_regclass(). (Tatsuo Ishii)

      Even though pgpool_regclass() exists, if pgpool cannot execute the
      function, the connection to backend hangs. You can reproduce the problem
      by just dropping  the execute privilege from pgpool_regclass and do some
      insert in native replication mode.

      The problem is reported in bugtrack #53.

      #53 pgpool_regclass hangs all connections
      Date:     2013-04-04 13:35
      Reporter: tmandke
      http://www.pgpool.net/mantisbt/view.php?id=53

    - Fix error message mistakes in detect_postmaster_down_error(). (Tatsuo Ishii)

      For example, "LOG: detect_stop_postmaster_error: detect_error error" is
      fixed to "LOG: detect_postmaster_down_error: detect_error error", and so on.

===============================================================================

                        3.1.6 (hatsuiboshi) 2013/2/8

* Version 3.1.6

      This is a bugfix release against pgpool-II 3.1.5

    __________________________________________________________________

* Bug fixes

    - Fix race condition when using md5 authentication. (Tatsuo Ishii)

      The file descriptor to pool_passwd is opened in pgpool main and pgpool
      child inherits it. When concurrent connections try to authenticate md5
      method, they call pool_get_passwd and seek the fd and cause random md5
      auth failure because underlying fd is shared. Fix is, let individual
      pgpool child open the file by calling pool_reopen_passwd_file.

      Problem reported and analyzed by Jason Slagle in pgpool-general:1141.

      [pgpool-general: 1141] Possible race condition in pool_get_passwd
      From: Jason Slagle
      Date: Sun, 28 Oct 2012 01:12:52 -0400
      http://www.sraoss.jp/pipermail/pgpool-general/2012-October/001160.html

    - Fix hung up while repeating pcp_attach_node and pcp_detach_node
      (Tatsuo Ishii)

      When node status is changed by pcp_attach_node and pcp_detach_node,
      failover() sends SIGUSR1 to pcp_child process expecting it exits to
      refresh node status. In this situation lots of pgpool children exit and
      produce SIGCHLD as well. The SIGCHLD handler reaper() tries catch all
      SIGCHLD but sometimes it fails depending on the system load and timing.
      If SIGCHLD produced by pcp child is not caught, the process becomes
      zombie and never restarted.

      This problem is reported in bug track #32 (by oleg_myrk) etc.

      #32 PGPool hangs on pcp_attach/detach
      Reporter: oleg_myrk
    　Date: 2012-10-24 00:01
      http://www.pgpool.net/mantisbt/view.php?id=32

    - Fix pool_send_severity_message() not to use uninitialized memory.
      (Tatsuo Ishii)

      It cause a segmentation fault.
      Reported in Bug #33's attached valgrind output by dudee.

      #33 pgpool-II 3.2.1 segfault
      Reporter: dudee
      Date: 2012-10-30 19:16
      http://www.pgpool.net/mantisbt/view.php?id=33

    - Add a description about "-f" to help message. (Tatsuo Ishii)

    - Fix reaper() not to exit wait3() loop when catches pcp or worker child
      exit event. (Tatsuo Ishii)

      Otherwise reaper() mistakenly ignore some process exit event and make a
      risk of creating zombie process and forgetting to create new process.

      Problem reported and fix suggested by Goto in [pgpool-general-jp: 1123].
      http://www.sraoss.jp/pipermail/pgpool-general-jp/2012-November/001122.html
      (in Japanese)

    - Fix pool_search_relcache() to use MASTER or MASTER_NODE_ID macro, rather
      than REAL_MASTER_NODE_ID. (Tatsuo Ishii)

      In case node 0 fail back in streaming replication mode, pgpool does not
      restart child process.  So REAL_MASTER_NODE_ID looks for node 0 con info,
      which is not present until new connection to backend made. Thus referring
      to node con info results in segfault. MASTER or MASTER_NODE_ID are safe in
      this situation because they look at cached former master node id.

    - Fix long standing bug "portal not found" error when replication delay
      is too much in streaming replication mode. (Tatsuo Ishii)

      The bug had been there since the delay threshold was introduced.

      We changed destination DB node if delay threshold exceeds in bind,
      describe and execute. However, if parse sends to different node, bind,
      describe or execute will fail because no parsed statement or portal
      exists.  Solution is, not to send to different parse node even
      if delay threshold is too much.

    - Fix pg_md5 to output "\n" after user inputs password. (Yugo Nagata)

    - Fix child_exit() to not call send_frontend_exits() if there's no
      connection pool. (Tatsuo Ishii)

      Otherwise, it segfaults because send_frontend_exits() refers to objects
      pointed to by pool_connection_pool. Per bug track #44 by tuomas.

      #44 pgpool went haywire after slave shutdown triggering master failover
      Reporter: tuomas
      Date: 2012-12-11 00:33
      http://www.pgpool.net/mantisbt/view.php?id=4

    - Fix read_startup_packet() to reset alarm and free StartupPacket when
      pool_read() returns 0 which means incorrect packet length. (Nozomi Anzai)

      Previously, authentication timeout occurs when connected by a program
      monitoring the pgpool port.It is reported in bug track #35 by tuomas.

      #35 Authentication is timeout
      Reporter: tuomas
      Date: 2012-11-20 11:54
      http://www.pgpool.net/mantisbt/view.php?id=3

    - Fix long standing bug with pool_open(). (Tatsuo Ishii)

      It initializes wrong buffer pointer. Actually this is harmless because the
      pointer is initialized by prior memset() call, though.

    - Modify documents to correct information of whether a certain parameter
      change requires restart. (Yugo Nagata)

    - Add pool_passwd option to pgpool.conf.sample*, and documents. (Yugo Nagata)

===============================================================================

                        3.1.5 (hatsuiboshi) 2012/10/12

* Version 3.1.5

      This is a bugfix release against pgpool-II 3.1.4

    __________________________________________________________________

* Bug fixes

    - Fix read_startup_packet. (Tatsuo Ishii)

      If packet length is lower than 0, it should
      have returned immediately. Otherwise it would cause memory allocation
      error later on.  per pgpool-general:886.
      Also add canceling alarm.

    - Add NOTICE message handling to s_do_auth. (Tatsuo Ishii)

      Without this, health check responses false alarm and causes failover.
      per bug track:
      http://www.pgpool.net/mantisbt/view.php?id=25
      Also allow to receive ready for query packet *not* right after backend
      keydata.  I'm not sure if this could happen in the real world but the
      protocol seems to allow this.

    - Remove unnecessary/confusing debug log from s_do_auth.(Tatsuo Ishii)

    - Fix infinite loop in SSL mode. When there's pending data in SSL layer
      of frontend, pool_process_query() checks pending data in backend.
      (Tatsuo Ishii)

      If there's non, it loops again and checks frontend/backend receive buffer
      by using is_cache_empty(). Unfortunately it first checks pending data
      in SSL layer of frontend, thus goes to backend data and checks again
      (infinite loop).
      The solution is, if there's pending data in SSL layer of frontend and
      query is not in progress, call ProcessFrontendResponse() to process new
      request from frontend.

    - Fix is_system_catalog to use pgpool_regclass if available.
      (Tatsuo Ishii)

    - Fix memory leak in pool_get_insert_table_name(). (Tatsuo Ishii)

      If session context's memory contex is used for nodeToString(), memory is
      not freed until session ends.

    - Fix possible memory leak in nodeToString(). (Tatsuo Ishii)

      Since the memory context could be session context, memory used for
      String object may be considerable if user session continues for hours or
      days.
      See bug track #24 for more details.

    - Fix long standing problem with do_query(). (Tatsuo Ishii)

      When 1) extended protocol used and 2)unnamed portal is used and 3) no
      explicit transaction is used, user's unnamed portal is removed by Sync
      message.
      This is because Sync message closes transaction and unnamed portal is
      removed. This leads to "portal "" does not exist" error.

      Fix is, use "Flush" message instead of Sync. Main difference between
      using Sync and Flush is, Flush does not return Ready for Query message.
      So do_query() does not return until all expected responses are returned.
      It seems the order of messages returned from backend is random, and
      do_query () manages it by using state bits.

===============================================================================

                        3.1.4 (hatsuiboshi) 2012/08/06

* Version 3.1.4

      This is a bugfix release against pgpool-II 3.1.3.

    __________________________________________________________________

* General

      - Adopt PostgreSQL 9.2. (Tatsuo Ishii)

    __________________________________________________________________

* Bug fixes

      - Fix pool_send_and_wait() to send or not to send COMMIT / ABORT
        depending on the transaction state on each node. (Tatsuo Ishii)

        It is possible that only primary is in an explicit transaction but
        standby is not in it if multi statement query has been sent.
        Per bug report [pgpool-general-jp: 1049].

      - Fix load balance in Solaris. (Tatsuo Ishii)

        Problem is, random() in using random() in Solaris results in strange
        load balancing calculation.
        Use srand()/rand() instead although they produce lesser quality random
        Problem reported at [pgpool-general: 396].

          [pgpool-general: 396] strange load balancing issue in Solaris
          http://www.pgpool.net/pipermail/pgpool-general/2012-April/000397.html

      - Add params to the result of "SHOW pool_status": backend_data_directory,
        ssl_ca_cert, ssl_ca_cert_dir. (Nozomi Anzai)

      - Fix segfault of pcp_systemdb_info not in parallel mode. (Nozomi Anzai)

      - Fix "unnamed prepared statement does not exist" error. (Tatsuo Ishii)

        This is caused by pgpool's internal query, which breaks client's
        unnamed statements. To fix this, if extended query is used, named
        statement/portal for internal are used for internal query.

      - Fix is_system_catalog(). Its relcache was accidently defined as
        "session local". (Tatsuo Ishii)

      - Fix hangup when query conflict occurs in Hot-Standby mode.
        (Yugo Nagata)

        Query example to reproduce:

            (S1) BEGIN;
            (S1) SELECT * FROM t;
            (S2) DELETE FROM t;
            (S2) VACUUM t;

      - Improve reading and writing pid_file. (Tatsuo Ishii)

      - Fix pool_process_query() bug reported in [pgpool-general: 672].
        (Tatsuo Ishii)

        This is caused by the function waits for primary node which does not
        have pending data, while standbys have pending data.

          [pgpool-general: 672] Transaction never finishes
          http://www.pgpool.net/pipermail/pgpool-general/2012-June/000676.html

      - Fix wait_for_query_response() not to send param status to frontend if
        frontend is NULL. (Tatsuo Ishii)

        This could happen while processing reset_query_list and occur crash.

      - Fix bug with treatment of BEGIN TRANSACTION in master/slave mode.
        (Tatsuo Ishii)

        Original complain is [pgpool-general: 714].
        From 3.1, pgpool-II sends BEGIN.. to all DB nodes. Of course we cannot
        send BEGIN TRANSACTION READ WRITE to standby nodes.
        Problem is, we did not check BEGIN WORK ISOLATION LEVEL SERIALIZABLE;
        and sent to standby nodes. Of course this is wrong, since it's not
        allowed to run transactions in serializable mode on standby nodes.
        So added check for BEGIN WORK ISOLATION LEVEL SERIALIZABLE case.

          [pgpool-general: 714]
          Load Balancing / Streaming Replication / Isolation Level serializable
          http://www.pgpool.net/pipermail/pgpool-general/2012-July/000719.html

      - Fix send_to_where() to send the query to only primary if the it is like
        SET TRANSACTION ISOLATION LEVELSERIALIZABLE etc. (Tatsuo Ishii)

        Case in streaming replication mode. Previously, it was sent to not only
        primary but also to standby and of course this causes an error.
        Similar SQLs are:

         SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL
         SERIALIZABLE or SET transaction_isolation TO 'serializable'
         SET default_transaction_isolation TO 'serializable'

        Original complain is [pgpool-general: 715].

          [pgpool-general: 715]
          Re: Load Balancing / Streaming Replication / Isolation Level
          serializable
          http://www.pgpool.net/pipermail/pgpool-general/2012-July/000720.html

===============================================================================

                        3.1.3 (hatsuiboshi) 2012/04/23

* Version 3.1.3

      This is a bugfix release against pgpool-II 3.1.2.

    __________________________________________________________________

* Bug fixes

      - Add m4 files. This should prevent compiling problem on older
        OS's. (Tatsuo Ishii)

      - Fix to handle failover properly in detect_postmaster_down_error().
        (Tatsuo Ishii)

        It is possible that it fails to read backend socket after detecting
        backend errors and before actually detaching the backend.

      - Fix bug that the process exits before unlocking semaphore by a
        signal interrupt. (Tatsuo Ishii)

      - Fix a memory leak in case of reset_query. (Tatsuo Ishii)

      - Fix pool_ssl_read() to deal with large data reading. (Tatsuo Ishii)

        Original complain is here:
        http://www.pgpool.net/pipermail/pgpool-general/2012-March/000299.html

      - Fix deadlock by enabling log_destination = syslog. (Tatsuo Ishii)

        Reported in bug tracker http://www.pgpool.net/mantisbt/view.php?id=9.
        Patch provided by Gilles Darold.

      - Allow to use multi statement in master/slave mode. (Tatsuo Ishii)

        From 3.1 transactional statements such as "BEGIN" are sent to not only
        primary but also standbys. This brings an unfortunate side effect: if
        the multi statement is "BEGIN;DELETE FROM table;END", this will be
        sent to standby as well and cause an error because standby does notallow
        write SQL. So fix is, if a query is a multi statement one, then send it
        to primary only.

      - Allow to have private cache of master node id. (Tatsuo Ishii)

        When master goes down running pgpool children look into NULL pointer
        because the process does not connect to the new master yet. The private
        cache returns the old master node id and will avoid the situation.

        Per bug reported in http://www.pgpool.net/mantisbt/view.php?id=51

      - Fix pool_start_query() so that it uses my_master_node_id instead of
        REAL_MASTER_NODE_ID for initial virtual_master_node_id. (Tatsuo Ishii)

        Real master node could be changed while pgpool is running in streaming
        replication mode. Previously it is assigned REAL_MASTER_NODE_ID, which
        could have no connections after fail over and cause segfault.

      - Fix pool_setall_node_to_be_sent() to use private_backend_status instead
        of BACKEND_INFO macro. (Tatsuo Ishii)

        It is possible that while processing, the node returned by BACKEND_INFO
        is not usable any more.

      - Fix failover(). (Tatsuo Ishii)

        Before it only restarts worker child only when pgpool child do not need
        restart. This is wrong. We need to restart worker child in any case.
        Otherwise it continues to send replication time lag check request to down
        the node.

      - Fix debug log message so that it does not contain null characters.
        (Toshihiro Kitagawa)

      - Fix SimpleQuery() so that it restores parser memory context when:
          1) Builtin show commands are used
          2) Parallel query mode
          3) Query cache is used
        (Tatsuo Ishii)

      - Fix hangup when PREPARE statement causes error. (Toshihiro Kitagawa)

        This issue was reported by Tomonari Katsumata:
        Subject: [pgpool-general: 121] question of pgpool's behavior

      - Add doc/pgpool-fr.html to Makefile.am. (Tatsuo Ishii)

        This had been forgotten when the doc was added.

      - Fix  hangup during md5 authentication that occurs in daemon mode
        and log_destination is 'syslog'. (Yugo Nagata)

        Reported in bug tracker http://www.pgpool.net/mantisbt/view.php?id=2.

===============================================================================

                        3.1.2 (hatsuiboshi) 2012/01/31

* Version 3.1.2

      This is a bugfix release against pgpool-II 3.1.1.

    __________________________________________________________________

* Bug fixes

      - Fix to recognize READ UNCOMMITTED and REPEATABLE READ of transaction
        isolation levels. (Tatsuo Ishii)

      - Fix infinite loop reported in this thread (Tatsuo Ishii):
        http://www.pgpool.net/pipermail/pgpool-general/2011-December/000099.html

        It was not considered the case that, when received buffer in primary was
        empty but the one in a standby was not, the standby spontaneously sent
        packet to pgpool.
        This could happen when, for example, reloading postgresql.conf.
        The fix is that such buffer in standby is discarded.

===============================================================================

                        3.1.1 (hatsuiboshi) 2011/12/06

* Version 3.1.1

      This is a bugfix release against pgpool-II 3.1.

    __________________________________________________________________

* Bug fixes

      - Fix add_regex_pattern(). It does not allocate enough memory
           for each black/white_function_list items. The function adds
           "^" and "$" to each function items which do not contain those
           characters. Unfortunately the function forgot to add extra 2
           bytes for those characters. This may lead to memory corruption
           errors when pgpool starting up.

      - Fix error message of check_replication_time_lag(Tatsuo
        Ishii). It emitted wrong error message when it failed to
        connect to PostgreSQL while checking streaming replication
        delay. Because it does not use health_check_user anymore.

      - Fix memory leak(Toshihiro Kitagawa). This is essentially same
          as the fix made for 3.0.5(commit
          19a4ea9215da0b61728741fc0da2271958b09238).

      - Major cleanup for strncpy(Tatsuo Ishii). There are several
          places where strncpy() is used. Problem is some of them do not
          consider the case when copy length == buffer size. In this case
          copied buffer is not null terminated and may cause tons of
          problems later.  To fix this, most of them are replaced by
          strlcpy().

      - Update cached backend status whenever possible(Tatsuo Ishii).
          This solves the problem of follow_master_command not being
          able to lookup backend status correctly which was reported by
          Jeff Frost: Subject: [Pgpool-general] diagnosing BackendError
          from pcp_recovery_node To: pgpool-general@pgfoundry.org Date:
          Wed, 05 Oct 2011 15:15:07 -0700

      - Fix buffer overrun problem when pcp password is longer than
        32(Tatsuo Ishii).

      - Remove PGDLLIMPORTI which is only necessary for Windows
          and cause a problem for non gcc. Patch contributed by Ibrar Ahmed.

===============================================================================

                        3.1 (hatsuiboshi) 2011/09/08

* Version 3.1

      This is the first version of pgpool-II 3.1 series.
      That is, a "major version up" from 3.0 series.

    __________________________________________________________________

* Incompatible changes

      - Change the lock method of insert_lock. The previous insert_lock uses
        row locking against the sequence relation, but the current one uses
        row locking against pgpool_catalog.insert_lock table. The reason is
        that PostgreSQL core developers decided to disallow row locking
        against the sequence relation to avoid an internal error which it
        leads. So creating insert_lock table in all databases which are
        accessed via pgpool-II beforehand is required. If does not exist
        insert_lock table, pgpool-II locks the insert target table. This
        behavior is same as pgpool-II 2.2 and 2.3 series. If you want to use
        insert_lock which is compatible with older releases, you can specify
        lock method by configure options: --enable-sequence-lock,
        --enable-table-lock(Toshihiro Kitagawa)

      - Deprecate backend_socket_dir. Instead, if backend_hostname starts
        with '/' it is regarded the as path to Unix domain. If backend_hostname
        is left empty, then default Unix domain path(/tmp) is used. This
        follows the convention of libpq interface. Patch contributed by
        Jehan-Guillaume (ioguix) de Rorthais.

      - Now "pgpool_walrecrunning()" was not used. pgpool-II used to consider
        the node that is promoted a primary node using the function. Now,
        pgpool-II waits for completing of the promotion to primary node
        because it did not work as we intended. But we still have a problem
        that pgpool-II waits while recovery_timeout, when there is no primary
        node(Toshihiro Kitagawa)

      - Add node_id to each PostgreSQL DB node info in the output of
        show pool_nodes(Jean-Paul Argudo)

      - Change the handling of sequence functions(nextval, setval) so that
        they completely obey setting of black/white_function_list. They were
        always handled as write functions before(Toshihiro Kitagawa)

    __________________________________________________________________

* New features

      - Add syslog support. Patch contributed by Gilles Darold. Review and
        editing by Guillaume Lelarge.

      - Adapt application_name introduced in PostgreSQL 9.0. When reusing
        connection, send application_name in the startup packet to backend
        and send parameter status to frontend(Tatsuo Ishii)

      - Add relcache_expire directive to control the expiration of the
        internal system catalog cache. ALTER TABLE might make these
        cache values obsoleted and the new directive will make the risk
        lower(Tatsuo Ishii).

      - Add follow_master_command directive. This directive specifies a
        command to run in master/slave streaming replication only after
        a master failover. Patch contributed by Gilles Darold.

      - Add pcp_promote_node command. This command promotes a new master
        node to pgpool-II. This can use in master/slave streaming replication
        only. Patch contributed by Gilles Darold.

      - Add pcp_pool_status command which produces similar output of show
        pool_status. Also C API for this command is added. Patch
        contributed by Jehan-Guillaume (ioguix) de Rorthais.

      - Add new per backend directive "backend_flag". This controls per
        backend behavior. Currently "ALLOW_TO_FAILOVER" or
        "DISALLOW_TO_FAILOVER" are allowed(Tatsuo Ishii)

      - Add health_check_password directive, but is not yet implemented
        (Nicolas Thauvin)

      - Add sr_check_period, sr_check_user and sr_check_password directives.
        These are used for streaming replication delay checking and
        determining primary node(Tatsuo Ishii)

      - Add --username(or -u) option to pg_md5 command. This allows to manage
        users which do not have UNIX accounts. Japanese document change by
        Tatsuo Ishii(Nicolas Thauvin)

      - Add pgpool_adm functions to pgpool_adm/. These are user-defined
        functions written in C language which work like pcp commands
        (Jehan-Guillaume (ioguix) de Rorthais)

      - Add Simplified Chinese version of documents(Huang Jian, Sun Peng)

      - Add SQL files to uninstall functions to sql/(Nicolas Thauvin)

      - In master/slave mode, SELECTs to unlogged table execute only on
        master/primary(Toshihiro Kitagawa)

    __________________________________________________________________

* Bug fixes

      - Fix bug which cannot use the cursors of JDBC driver on standby
        node. The transaction commands come to be sent to all nodes by
        this fix in master/slave mode(Toshihiro Kitagawa)

      - Fix bug with the handling of empty queries. The empty queries
        come to be handled the same as SELECT queries. This fix allows
        load-balance after the empty query(Toshihiro Kitagawa)

      - Fix insert_lock so that it works correctly even if the column
        definition such as "DEFAULT nextval(('"x_seq"'::text)::regclass)"
        (Toshihiro Kitagawa)

      - Fix pcp_attach_node command so that it emits error message while
        doing failover(Toshihiro Kitagawa)

      - Fix log message which is emitted when pgpool-II cannot parse the
        query in the extended query protocol so that it shows the query
        (Toshihiro Kitagawa)

      - Fix description about backend_weight inpgpool-II manual. It can
        be changed by reloading pgpool.conf(Tatsuo Ishii)

      - Fix and enhance wording in English tutorial document.
        Fix suggested by Huang Jian(Tatsuo Ishii)

      - Fix bug which does not update the node status when reattaching the
        node in raw mode(Guillaume Lelarge)

      - Fix incorrect calculation of the replication delay in streaming
        replication mode(Tatsuo Ishii)

      - Replace wrong function name "notice_backend_error" with correct one
        "degenerate_backend_set" in the failover log message(Tatsuo Ishii)

      - Remove unnecessary logging at the end of pgpool.conf parsing(Tatsuo Ishii)

      - Fix possible crash of pgpool/worker child after attaching new backend.
        Fix suggested by Gurjeet Singh(Tatsuo Ishii)

      - Fix bug that SELECTs which have subquery with FOR SHARE/UPDATE clause
        are sent to slave/standby(Tatsuo Ishii)

      - Fix bug which rewriting timestamp of default value fails in PREPARE
        statements. This used to work but was broken in 3.0(Toshihiro Kitagawa)

      - Fix fail to compile pcp commands on the environment without
        getopt_long()(Tatsuo Ishii)

      - Fix crash of pgpool child when frontend connects if in raw mode,
        enable_hba is off and more than 2 backends(Toshihiro Kitagawa)

      - Fix some memory leaks(Toshihiro Kitagawa)

    __________________________________________________________________

* Enhancements

      - Enhance online recovery in streaming replication mode.
        Now restarting pgpool-II children is avoided when recovery finished. So
        existing sessions can be continued while doing online recovery(Tatsuo Ishii)

      - pcp_attach_node does not disconnect existing sessions in
        streaming replication mode. In other mode, pcp_attach_node
        still disconnects existing sessions(Tatsuo Ishii).

      - Import PostgreSQL 9.0 parser. This allows to use CREATE INDEX with
        implicit index name, which is new in 9.0. Patch contributed by
        Akio Ishida.

      - Allow to use regular expressions in black and white function list.
        Patch contributed by Gilles Darold. Patch reviewed by Guillaume Lelarge.

      - Reorganize pgpool.conf sample files so that they are easier to read
        (Guillaume Lelarge)

      - Add <a name="..."> tags into all parameters in the pgpool-II user
        manual(Haruka Takatsuka)

      - Enhance online recovery documents in streaming replication(Tatsuo Ishii)

      - Change the function to check the replication delay in streaming
        replication mode. Currently, pgpool uses
        pg_last_xlog_replay_location() instead of
        pg_last_xlog_receive_location(). Fix suggested by Anton Yuzhaninov
        (Tatsuo Ishii)

      - Allow time stamp rewriting to work with arbitrary expression in
        default value of a column. Before we detected anything including
        now() then simply replaced it to now(). This will lead to wrong
        rewriting of default value. for example, timezone('utc'::text, now()).
        Note that, however, this only adopts to simple queries. Extended
        protocols(for example Java, PHP PDO) or SQL "PREPARE" still remain
        same(Tatsuo Ishii)

      - Enhance the error message which is emitted when failed to check
        replication delay(Nicolas Thauvin)

      - Change error message "do_md5: read_password_packet failed" into debug
        level(Toshihiro Kitagawa)

      - Allow to compile pgpool-regclass() against PostgreSQL 9.1(Tatsuo Ishii)

      - Update and sync pgpool-II manuals of English version and Japanese
        version(Tatsuo Ishii)


===============================================================================
3.0 Series (2013/07/30 - )
===============================================================================

                        3.0.20 (umiyameboshi) 2016/02/05

* Version 3.0.20

    This is a bugfix release against pgpool-II 3.0.19.

    This is the final release of the series. pgpool-II 3.0 has reached
    End of Life, and is no longer maintained and does not receive any
    updates.

    __________________________________________________________________

* Bug fixes

    - doc: Fix misinformation regarding load balancing in docs (Tatsuo Ishii)

      In streaming replication mode, DECLARE, FETCH, CLOSE and SHOW are sent
      to primary node only. Pointed out in [pgpool-general-jp: 1378].

    - Issue fsync() when writing pgpool_status (Tatsuo Ishii)

      This ensures that pgpool_status is saved to permanent storage and
      allow to survive after system crash.

    - doc: Fix wrong description about log_standby_delay in the document
      (Yugo Nagata)

    - Fix bug with "SET TRANSACTION READ ONLY" (Tatsuo Ishii)

      Pgpool-II remembers that non read only queries (including SET) were
      executed in an explicit transaction and adds a "writing transaction"
      mark to the transaction. The mark affects the query routing behavior
      of pgpool-II while running in streaming replication mode. Pgpool-II
      starts sending queries to the primary after the mark is set. Because
      the effect of writing queries may appear on standbys after some delay
      in streaming replication mode, it is safer to route read queries to
      the primary after the mark is set.

      However there's oversight here. "SET TRANSACTION READ ONLY" does no
      data modification and should be treated as an exception.

      Per bug #157.

    - Fix FATAL error with reloading (Tatsuo Ishii)

      While reloading pgpool.conf, the number of DB nodes is tentatively set
      to 0, then counted up until reaching to the actual number of backends
      by the pgpool main process. Unfortunately the variable was on the
      shared memory and it confused pgpool child process when they were using
      the variable and this caused FATAL error.

      Per bug #156 report by harukat.

    - Ignore close statement/portal request if they do not exist (Tatsuo Ishii)

      In this case just returns a close complete message to client.
      This is a back port of the following commit from pgpool-II 3.4:

      1a37e1c35bd8b6f10f524693bbcb7b51f73b4bf0

===============================================================================

                        3.0.19 (umiyameboshi) 2015/07/24

* Version 3.0.19

    This is a bugfix release against pgpool-II 3.0.18.

    __________________________________________________________________

* Bug fixes

    - Fix "cannot find xlog functions" error in pgpool-recovery
      (Muhammad Usama)

      The argument data type of PostgreSQL's pg_xlogfile_name() function
      has been changed from text to pg_lsn since PostgreSQL 9.4. And
      pgpool-recovery was still trying to locate the function by old
      signature.

    - Do not send a query for checking insert lock in non replication mode
      with extended query (Tatsuo Ishii)

===============================================================================

                        3.0.18 (umiyameboshi) 2015/04/08

* Version 3.0.18

    This is a bugfix release against pgpool-II 3.0.17.

    __________________________________________________________________

* Bug fixes

    - Enlarge POOLCONFIG_MAXDESCLEN to 80 (Tatsuo Ishii)

      This is used in show pool_status command and limits the length of
      parameter description.  Unfortunately recovery_timeout description is
      64 chars, which is 1 byte longer than former definition of the macro.

    - Support SSL certificate chains in the certificate file for incoming
      frontend connections (Muhammad Usama)

    - Fix a problem with pcp_detach_node about graceful node detach (Muhammad Usama)

      When graceful node detach is requested gracefully, pcp_detach_node should
      check if it is allowed to process detach_node command on the particular
      node before blocking the incoming connections and closing the existing
      connections.

===============================================================================

                        3.0.17 (umiyameboshi) 2015/02/05

* Version 3.0.17

    This is a bugfix release against pgpool-II 3.0.16.

    __________________________________________________________________

* Bug fixes

    - doc: Describe explicitly that the number of slave nodes is not
      necessarily 1 (Tatsuo Ishii)

    - Fix uninitialized variable (Tatsuo Ishii)

      Per Coverity 1234603.

    - doc: Fix missing release note entries in the previous release
      (Tatsuo Ishii)

    - Fix node id range check bug in trigger_failover_command(). (Tatsuo Ishii)

      The node id should be lower than NUM_BACKENDS. Probably harmless since
      callers never pass node ids greater or equal to NUM_BACKENDS.

    - Fix to disable debug mode by reloading config (Yugo Nagata)

      Per bug #114
      http://www.pgpool.net/mantisbt/view.php?id=114

===============================================================================

                        3.0.16 (umiyameboshi) 2014/09/05

* Version 3.0.16

    This is a bugfix release against pgpool-II 3.0.15.

    __________________________________________________________________

* Bug fixes

    - Fix a typo of pgpool.spec (Yugo Nagata)

    - Fix bug that worker child process keeps failing when there's no
      primary backend (Tatsuo Ishii)

      Problem identified and fix contributed by Junegunn Choi.

      See [pgpool-hackers: 471] for more details.

    - Close listen socket when smart shutdown request is made (Tatsuo Ishii)

      When smart shutdown process starts, pgpool children still listen on
      the port and clients can send further connection requests which fail
      in the end. Which is not only waste of time, but also prevents a load
      balancer which sits in front of pgpool from realizing the pgpool is
      going down.

      Problem analyzed and patch provided by Junegunn Choi in [pgpool-hackers
      474], and enhanced to take care not only inet domain socket but UNIX
      domain socket by Tatsuo Ishii.

    - doc: Add cautions that recovery commands are killed by statement_timeout
      of PostgreSQL. (Tatsuo Ishii)

    - doc: Remove old restriction description which is no longer true
      (Tatsuo Ishii)

    - Fix return type of text_to_lsn() function (Yugo Nagata)

      This caused compile warning.

    - Fix file descriptor leak when daemonize. (Tatsuo Ishii)

      Per Coverity 1111471.

    - Fix memory leak. (Tatsuo Ishii)

      Per Coverity 1111442.

    - Fix pgpool.init's long-standing bug of stop/restart failure
      (Yugo Nagata)

      In previous, pgpool.init uses killproc for stopping pgpool, but there
      are several problems. In the new version, "pgpool -m fast stop" is
      used in stop command.

      Original patch contributed by Ryan DeShone and modified by Yugo Nagata.

      See [pgpool-hackers: 239][pgpool-hackers: 512].

    - Disable statement_timeout of PostgreSQL while executing online recovery
      (Tatsuo Ishii)

      Online recovery may take very long time and user may enable statement
      timeout. To prevent online recovery canceled by statement timeout,
      disable statement timeout in the connection used by online recovery.

      See [pgpool-general: 2919] for more details.

    - Remove unnecessary call to pool_shmem_exit() which removes semaphore
      when it shouldn't (Tatsuo Ishii)

      exit_handler checks if the process is parent or not. This is
      good. However, even if it is a child process, it calls
      pool_shmem_exit() which removes semaphore and shmem when it should
      not. It should be called only from parent process.

      Per bug #102.
      http://www.pgpool.net/mantisbt/view.php?id=102

===============================================================================

                        3.0.15 (umiyameboshi) 2014/03/24

* Version 3.0.15

    This is a bugfix release against pgpool-II 3.0.14.

    __________________________________________________________________

* Bug fixes

    - doc: Add mention about "listen queue" and how to increase the "backlog"
      in the num_init_children section. (Tatsuo Ishii)

    - Fix bad performance of unlogged tables detection code. (Tatsuo Ishii)

      Pointed out at [pgpool-hackers: 435][[pgpool-general:2325].

    - Fix primary node detection logic. (Tatsuo Ishii)

      There's a possibility that primary node is not detected. This happens
      in following situation.  node 0: primary, node 1: standby. Node 0 goes
      down. Health checking detects the fact but local status is not updated
      yet. Primary node finding (find_primary_node) runs. Node 0's status is
      yet healthy. Because find_primary_node fails to connect to node 0, it
      immediately returns -1 and fails to find that fact that node 1 is now
      primary.

      Fix is just continuing to look for primary node when fails to connect
      to a node.

      Per [pgpool-general: 2409].

    - Fix jdbc DML fails when operated in raw mode and auto commit is off.
      (Tatsuo Ishii)

      This is reported in bug #92.

    - Avoid to send queries to unrelated nodes in streaming replication mode.
      (Tatsuo Ishii)

      Pgpool-II sends certain queries, such as BEGIN, END and SET commands to
      all of DB nodes. However in streaming replication mode, only primary
      node and at most one standby node are only concerned (if primacy node
      is selected as the load balance node, only 1 node is concerned).

      See [pgpool-hackers: 464] for more details.

    - Fix possible buffer overrun problem and memory leak. (Tatsuo Ishii)

      Per Coverity 1111465 and 1111482.

    - Fix freeing NULL. (Tatsuo Ishii)

      Per Coverity 1111384.

    - Fix memory leak. (Tatsuo Ishii)

      Per Coverity 1111446.

    - Fix a segmentation fault in parallel mode with system_db_hostname is
      empty (Yugo Nagata)

    - Fix to output debug messages in processing pgpool.conf with -d option
      (Yugo Nagata)

      Previously, some debug messages in pool_get_config() ware not output
      even when -d option was used.

    - Fix JDBC exception of prepared statement including now() in
      replication mode (Yugo Nagata)

      With JDBC, when a prepared statement is executed more than
      PrepareThreshold times, the statement is named and Describe message
      is sent after Parse. With named statement, pgpool rewrite now() to
      parameter in replication mode. Hence, rewritten query has additional
      parameter than original. In this case, ParameterDescription message
      sent to frontend (response of Describe) should include OIDs of the
      same number os original query's parameters. Otherwize, JDBC throws
      ArrayIndexoutOfBoundsException.

      This is reported in [pgpool-general-jp: 1192].

    - Fix backend error of prepared statement about table which has column whose
      default value is now() in replication mode (Yugo Nagata)

      When pgpool parses a named prepared statement with default now(),
      timestamps are replaced to additional parameters. So, Bind message also
      should included additional parameter format codes. However, when the
      number of original parameter was one, pgpool didn't handle this. This
      caused a error like "incorrect binary data format in bind parameter 2".

    - doc: Add description about parallel mode doesn't support PREPARE (Yugo Nagata)

      Per bug #93

===============================================================================

                        3.0.14 (umiyameboshi) 2013/12/06

* Version 3.0.14

      This is a bugfix release against pgpool-II 3.0.13.

    __________________________________________________________________

* Bug fixes

    - Fix incorrect time stamp rewriting in replication mode for certain time
      zones. (Tatsuo Ishii)

      Time stamp rewriting calls "SELECT now()" to get current time.
      Unfortunately the buffer for the current time is too small for certain
      time zones such as "02:30". Note that non-30-minutes-time-zone such as
      "0900" does not reveal the problem. This explains why we haven't the bug
      report until today.

      Bug reported in [pgpool-general: 2113] and fix provided by Sean Hogan.
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002142.html

    - Makefile: Replace pg_config by $(PG_CONFIG) in Makefiles so it can be
      overridden at build time when compiling for different PG major versions.
      (Tatsuo Ishii)

      Patch contributed by Christoph Berg ([pgpool-general: 2127]).
      http://www.sraoss.jp/pipermail/pgpool-general/2013-September/002156.html

    - configure: Remove -lcompat because it confuses FreeBSD per bug#15.
      (Tatsuo Ishii)
      http://www.pgpool.net/mantisbt/view.php?id=15

    - Fix segfault when pgpool.conf does not set log_standby_delay.
      (Tatsuo Ishii)

      This is caused by wrong initialization for log_standby_delay in
      pool_config.l.
      Per bug#74. http://www.pgpool.net/mantisbt/view.php?id=74

    - doc: Modify descriptions about restrictions of parallel mode
      Multiple rows INSERT using VALUES are not supported in parallel mode.
      (Yugo Nagata)

    - Avoid calling find_primary_node_repeatedly() when standby node goes
      down. (Tatsuo Ishii)

      This will reduce the time to failover. Per bug #75, patch modified by
      Tatsuo Ishii. http://www.pgpool.net/mantisbt/view.php?id=75

    - Fix error message in read_password_packet(). (Tatsuo Ishii)

    - Fix memory leak when do_query() fails in timestamp rewriting.
      (Tatsuo Ishii)

      For this purpose free_select_result() is changed to accept NULL argument.
      Per Coverity report "1111454, 1111455 Resource leak".

    - Fix target node selection logic when "DEALLOCATE portal|statement".
      (Tatsuo Ishii)

      When "DEALLOCATE portal|statement" is used and last prepared statement or
      portal was not found, target node selection map is not set. Probably this
      is not actually harmful because prepared statement or portal was not found
      is an error case. The bug was there since day 0.

      Per Coverity report "1111491 Structurally dead code".

    - Fix range check bug of MAX_NUM_BACKENDS in corner case. (Tatsuo Ishii)

      MAX_NUM_BACKENDS is the allowed max number of DB nodes (128, at this
      point). In reality, probably no one ever tried more than 128 DB nodes
      and that's the reason why nobody noticed.

      Per Coverity report "1111429, 1111430 and 1111431 Out-of-bounds write".

    - Fix that the script forgets to allow public access to pgpool_catalog.
      (Tatsuo Ishii)

      The bug prevents inserting data into user tables if pgpool_catalog is
      created in native replication mode.  The bug was there from day 1. I
      wonder why nobody noticed until today.
      Per [pgpool-general-jp: 1229].
      http://www.sraoss.jp/pipermail/pgpool-general-jp/2013-November/001228.html

    - Fix uninitialized variable in error case in pool_do_auth().
      (Tatsuo Ishii)

      If there's no valid backend, pgpool will return garbage pid to frontend in
      auth phase. Actually because no backend is available, frontend will be
      disconnected later on. So this is not harmless.
      Per Coverity report "1127331 Uninitialized scalar variable".

    - Fix to add node id range check when issue an error message using node
      id. (Tatsuo Ishii)
      Per Coverity report #1111433 "Out-of-bounds read".

    - Fix buffer overrun bug and resource leak bug of parse_copy_data().
      (Tatsuo Ishii)
      Per Coverity report 1111427 "Out-of-bounds write" and 1111453 "Resource
      leak".

    - Fix possible segfault in CopyDataRaws(). (Tatsuo Ishii)
      Coverity pointed out that if pool_get_id() returns an error, VALID_BACKEND
      will access out of array.
      Per Coverity report 1111413 "Memory - illegal accesses".

    - Fix strftime() usage in pool_pools(). (Tatsuo Ishii)

      The buffer is not large enough as expected by the second parameter. This
      is not harmless because the format string will not produce longer result
      string than the buffer.
      Per Coverity report 1111426 "Out-of-bounds access".

    - Fix resource leak in make_persistent_db_connection. (Tatsuo Ishii)

      For this purpose, new static function free_persisten_db_connection_memory
      is added.
      Per Coverity report #1111468.

===============================================================================

                        3.0.13 (umiyameboshi) 2013/09/06

* Version 3.0.13

      This is a bugfix release against pgpool-II 3.0.12.

    __________________________________________________________________

* Bug fixes

    - Fix a mistake in ssh command of doc/basebackup.sh (Tatsuo Ishii)

    - Fix a bug in parsing prepared statements with transaction handling in
      replication mode (Tatsuo Ishii)

      Parse() automatically starts a transaction for non SELECT query to keep
      consistency among nodes in replication mode. But this wasn't closed. If
      wrong query comes in, the transaction goes into an abort state but pgpool
      does not close the transaction. Thus next query causes error because the
      transaction is still in abort status.

      This problem was reported in [pgpool-general: 1877] by Sean Hogan.

      [pgpool-general: 1877] current transaction is aborted, commands ignored
      http://www.sraoss.jp/pipermail/pgpool-general/2013-July/001905.html

    - Fix typos of the japanese document (Yugo Nagata)

===============================================================================

                        3.0.12 (umiyameboshi) 2013/07/10

* Version 3.0.12

      This is a bugfix release against pgpool-II 3.0.11.

    __________________________________________________________________

* Bug fixes

    - Add mention about "-D" option to the man page. (Tatsuo Ishii)

    - Consider timeout waiting for completion of failback request in on line
      recovery (Tatsuo Ishii)

      This will prevent the situation that recovery operation continues forever
      and we cannot even shutdown pgpool-II main process. This could happen
      especially while executing follow master command.

    - Fix do_query() to not hang when PostgreSQL returns an error
      (Tatsuo Ishii)

      The typical symptom is "I see SELECT is keep on running according to
      pg_stat_activity". To fix this pgpool-II just exits the process and
      kill the existing connection.  This is not gentle but at this point I
      believe this is the best solution.

    - Fix bug with do_query which causes hung in extended protocol
      (Tatsuo Ishii)

      This problem could occur when insert lock is enabled and
      pgpool_catalog.insert_lock exists, See [pgpool-general: 1684] for more
      details.

      [pgpool-general: 1684] insert_lock hangs
      http://www.sraoss.jp/pipermail/pgpool-general/2013-May/001711.html

    - Fix unnecessary degeneration caused by error on commit (Tatsuo Ishii)

      In master slave mode, if master gets an error at commit, while other
      slaves are normal at commit, we don't need to degenerate any backend
      because it is likely that the "kind mismatch error" was caused by a
      deferred trigger.

    - Fix to register pgpool_regclass in pg_catalog schema (Tatsuo Ishii)

      This is necessary to deal with clients which restricts schema search path
      to pg_catalog only. Postgres_fdw is such a client.

    - Fix a potential crash in pg_md5 command (Muhammad Usama)

    - Fix a segmentation fault of a child process that occurs when a startup
      packet has no PostgreSQL user information (Yugo Nagata)

      You can reproduce it by

          $ psql -p 9999 -U ''

      If enable_pool_hba is on, a child process terminates by segmentation
      fault. Otherwise if enable_pool_hba is off, the error message is

          ERROR: pool_discard_cp: cannot get connection pool for user (null)
                 database (null)

      In both cases, psql terminates with no message on frontend.

      In the fixed version, if PostgreSQL user is not specified in startup packet,
      the message as following is output to both log and frontend. This is
      the same behavior as PostgreSQL.

          FATAL: no PostgreSQL user name specified in startup packet

    - Move ssl_ca_cert and ssl_ca_cert_dir descriptions to the SSL section
      (Yugo Nagata)

    - Add ssl_ca_cert and ssl_ca_cert_dir descriptions to the japanese document
      (Yugo Nagata)

    - Fix to verify the backend node number in pcp_recovery_node (Yugo Nagata)

      When an invalid number is used, null value is passed as an arguments
      of recovery script, and this causes a malfunction. In especially,
      rsync may delete unrelated files in basebackup scripts.

    - Fix reset query stuck problem. (Tatsuo Ishii)

      It is reported that reset query (DISCARD ALL etc.) occasionally does
      not finish and pgpool child remain waiting for reply from backend thus
      client cannot connect to pgpool.

      The cause of problem is not identified yet but if client suddenly
      closes connection to pgpool in the middle of query processing, backend
      may not accept the reset queries because they are not ready for query.

      The fix is, if frontend closes connection in unexpected way, query
      process loop immediately returns with new state:
      POOL_END_WITH_FRONTEND_ERROR and pgpool closes connection to
      PostgreSQL then goes back to new connection request waiting loop.

      Also, pgpool closes connections to backend when client_idle_limit is
      set and the idle limit.

      Per bug #107.
      http://www.pgpool.net/mantisbt/view.php?id=107

===============================================================================

                        3.0.11 (umiyameboshi) 2013/04/26

* Version 3.0.11

      This is a bugfix release against pgpool-II 3.0.10.

    __________________________________________________________________

* Buf fixes

    - Fix to show pool_passwd in "SHOW pool_status". (Yugo Nagata)

    - Fix long standing bug with timestamp rewriting code for processing
      extended protocol. (Tatsuo Ishii)

      Parse() allocate memory using palloc() while rewriting the parse
      message.  Problem is, the rewritten message was kept in the data which
      is managed by pool_create_sent_message() etc. The function assumes
      that all the data is in session context memory. However, palloc()
      allocates memory in query context of course, and gets freed later on
      when the query context disappears. And the function tries to free the
      memory as well, which causes various problems, including segfault and
      double free. To fix this, memory to store rewritten message is
      allocated using session context. The bug was there since pgpool-II 3.0
      was born.

      Problem analysis and patch contributed by Naoya Anzai.

      [pgpoolgenera-jp: 1146]. (in Japanese)
      http://www.pgpool.net/pipermail/pgpool-general-jp/2013-March/001145.html

    - Fix bug with md5 auth long user name handling. (Tatsuo Ishii)

      If user name is longer than 32 bytes, md5 authentication doesn't work.
      Problem reported in [pgpool-general: 1526] by Thomas Martin.

      [pgpool-general: 1526]
      [pgPool-II 3.2.3] MD5 authentication and username longer than 32 characters.
      http://www.pgpool.net/pipermail/pgpool-general/2013-March/001551.html

    - Fix to calculate replication delay only if standby server is behind from
      the primary server. (Yugo Nagata)

      When the primary server is behind from standby server, negative value of
      delay is calculated and the value is assigned to unsigned variable. It
      causes a log message informing negative replication delay. And what is
      worse, it also causes SELECT queries to be sent to the primary in load
      balance even though there are no replication delay in fact.

      The problem is reported and analyzed by Saitoh Hidenori in
      [pgpool-genera-jp: 1145].

      [pgpool-general-jp: 1145] (in Japanese)
      http://www.pgpool.net/pipermail/pgpool-general-jp/2013-March/001144.html

    - pgpool-recovery adopts PostgreSQL 9.3. (Tatsuo Ishii)

      Patch contributed by Asif Rehman. Slight editing by Tatsuo Ishii.

      [pgpool-hackers: 180]
      compile error in ppool-recovery
      http://www.pgpool.net/pipermail/pgpool-hackers/2013-April/000179.html

    - Fix pool_has_pgpool_regclass() to check execute privilege of
      pgpool_regclass(). (Tatsuo Ishii)

      Even though pgpool_regclass() exists, if pgpool cannot execute the
      function, the connection to backend hangs. You can reproduce the problem
      by just dropping  the execute privilege from pgpool_regclass and do some
      insert in native replication mode.

      The problem is reported in bugtrack #53.

      #53 pgpool_regclass hangs all connections
      Date:     2013-04-04 13:35
      Reporter: tmandke
      http://www.pgpool.net/mantisbt/view.php?id=53

    - Fix error message mistakes in detect_postmaster_down_error(). (Tatsuo Ishii)

      For example, "LOG: detect_stop_postmaster_error: detect_error error" is
      fixed to "LOG: detect_postmaster_down_error: detect_error error", and so on.

===============================================================================

                        3.0.10 (umiyameboshi) 2013/02/08

* Version 3.0.10

      This is a bugfix release against pgpool-II 3.0.9.

    __________________________________________________________________

* General

    - Fix race condition when using md5 authentication. (Tatsuo Ishii)

      The file descriptor to pool_passwd is opened in pgpool main and pgpool
      child inherits it. When concurrent connections try to authenticate md5
      method, they call pool_get_passwd and seek the fd and cause random md5
      auth failure because underlying fd is shared. Fix is, let individual
      pgpool child open the file by calling pool_reopen_passwd_file.

      Problem reported and analyzed by Jason Slagle in pgpool-general:1141.

      [pgpool-general: 1141] Possible race condition in pool_get_passwd
      From: Jason Slagle
      Date: Sun, 28 Oct 2012 01:12:52 -0400
      http://www.sraoss.jp/pipermail/pgpool-general/2012-October/001160.html

    - Fix pool_send_severity_message() not to use uninitialized memory.
      (Tatsuo Ishii)

      It cause a segmentation fault.
      Reported in Bug #33's attached valgrind output by dudee.

      #33 pgpool-II 3.2.1 segfault
      Reporter: dudee
      Date: 2012-10-30 19:16
      http://www.pgpool.net/mantisbt/view.php?id=33

    - Fix reaper() not to exit wait3() loop when catches pcp or worker child
      exit event. (Tatsuo Ishii)

      Otherwise reaper() mistakenly ignore some process exit event and make a
      risk of creating zombie process and forgetting to create new process.

      Problem reported and fix suggested by Goto in [pgpool-general-jp: 1123].
      http://www.sraoss.jp/pipermail/pgpool-general-jp/2012-November/001122.html
      (in Japanese)

    - Fix pool_search_relcache() to use MASTER or MASTER_NODE_ID macro, rather
      than REAL_MASTER_NODE_ID. (Tatsuo Ishii)

      In case node 0 fail back in streaming replication mode, pgpool does not
      restart child process.  So REAL_MASTER_NODE_ID looks for node 0 con info,
      which is not present until new connection to backend made. Thus referring
      to node con info results in segfault. MASTER or MASTER_NODE_ID are safe in
      this situation because they look at cached former master node id.

    - Fix long standing bug "portal not found" error when replication delay
      is too much in streaming replication mode. (Tatsuo Ishii)

      The bug had been there since the delay threshold was introduced.

      We changed destination DB node if delay threshold exceeds in bind,
      describe and execute. However, if parse sends to different node, bind,
      describe or execute will fail because no parsed statement or portal
      exists.  Solution is, not to send to different parse node even
      if delay threshold is too much.

    - Fix pg_md5 to output "\n" after user inputs password. (Yugo Nagata)

    - Fix child_exit() to not call send_frontend_exits() if there's no
      connection pool. (Tatsuo Ishii)

      Otherwise, it segfaults because send_frontend_exits() refers to objects
      pointed to by pool_connection_pool. Per bug track #44 by tuomas.

      #44 pgpool went haywire after slave shutdown triggering master failover
      Reporter: tuomas
      Date: 2012-12-11 00:33
      http://www.pgpool.net/mantisbt/view.php?id=44

    - Fix read_startup_packet() to reset alarm and free StartupPacket when
      pool_read() returns 0 which means incorrect packet length. (Nozomi Anzai)

      Previously, authentication timeout occurs when connected by a program
      monitoring the pgpool port.It is reported in bug track #35 by tuomas.

      #35 Authentication is timeout
      Reporter: tuomas
      Date: 2012-11-20 11:54
      http://www.pgpool.net/mantisbt/view.php?id=35

    - Fix long standing bug with pool_open(). (Tatsuo Ishii)

      It initializes wrong buffer pointer. Actually this is harmless because the
      pointer is initialized by prior memset() call, though.

    - Add a description about "-f" to help message. (Tatsuo Ishii)

    - Modify documents to correct information of whether a certain parameter
      change requires restart. (Yugo Nagata)

    - Add pool_passwd option to pgpool.conf.sample*, and documents. (Yugo Nagata)

===============================================================================

                        3.0.9 (umiyameboshi) 2012/10/12

* Version 3.0.9

      This is a bugfix release against pgpool-II 3.0.8.

    __________________________________________________________________

* General

    - Fix read_startup_packet. (Tatsuo Ishii)

      If packet length is lower than 0, it should
      have returned immediately. Otherwise it would cause memory allocation
      error later on.  per pgpool-general:886.
      Also add canceling alarm.

    - Add NOTICE message handling to s_do_auth. (Tatsuo Ishii)

      Without this, health check responses false alarm and causes failover.
      per bug track:
      http://www.pgpool.net/mantisbt/view.php?id=25
      Also allow to receive ready for query packet *not* right after backend
      keydata.  I'm not sure if this could happen in the real world but the
      protocol seems to allow this.

    - Remove unnecessary/confusing debug log from s_do_auth.(Tatsuo Ishii)

    - Fix infinite loop in SSL mode. When there's pending data in SSL layer
      of frontend, pool_process_query() checks pending data in backend.
      (Tatsuo Ishii)

      If there's non, it loops again and checks frontend/backend receive buffer
      by using is_cache_empty(). Unfortunately it first checks pending data
      in SSL layer of frontend, thus goes to backend data and checks again
      (infinite loop).
      The solution is, if there's pending data in SSL layer of frontend and
      query is not in progress, call ProcessFrontendResponse() to process new
      request from frontend.

    - Fix is_system_catalog to use pgpool_regclass if available.
      (Tatsuo Ishii)

    - Fix memory leak in pool_get_insert_table_name(). (Tatsuo Ishii)

      If session context's memory contex is used for nodeToString(), memory is
      not freed until session ends.

    - Fix possible memory leak in nodeToString(). (Tatsuo Ishii)

      Since the memory context could be session context, memory used for
      String object may be considerable if user session continues for hours or
      days.
      See bug track #24 for more details.

    - Fix long standing problem with do_query(). (Tatsuo Ishii)

      When 1) extended protocol used and 2)unnamed portal is used and 3) no
      explicit transaction is used, user's unnamed portal is removed by Sync
      message.
      This is because Sync message closes transaction and unnamed portal is
      removed. This leads to "portal "" does not exist" error.

      Fix is, use "Flush" message instead of Sync. Main difference between
      using Sync and Flush is, Flush does not return Ready for Query message.
      So do_query() does not return until all expected responses are returned.
      It seems the order of messages returned from backend is random, and
      do_query () manages it by using state bits.

===============================================================================

                        3.0.8 (umiyameboshi) 2012/08/06

* Version 3.0.8

      This is a bugfix release against pgpool-II 3.0.7.

    __________________________________________________________________

* General

      - Adopt PostgreSQL 9.2. (Tatsuo Ishii)

    __________________________________________________________________

* Bug fixes

      - Fix load balance in Solaris. (Tatsuo Ishii)

        Problem is, random() in using random() in Solaris results in strange
        load balancing calculation.
        Use srand()/rand() instead although they produce lesser quality random
        Problem reported at [pgpool-general: 396].

          [pgpool-general: 396] strange load balancing issue in Solaris
          http://www.pgpool.net/pipermail/pgpool-general/2012-April/000397.html

      - Fix segfault of pcp_systemdb_info not in parallel mode. (Nozomi Anzai)

      - Fix "unnamed prepared statement does not exist" error. (Tatsuo Ishii)

        This is caused by pgpool's internal query, which breaks client's
        unnamed statements. To fix this, if extended query is used, named
        statement/portal for internal are used for internal query.

      - Fix is_system_catalog(). Its relcache was accidently defined as
        "session local". (Tatsuo Ishii)

      - Improve reading and writing pid_file. (Tatsuo Ishii)

      - Fix pool_process_query() bug reported in [pgpool-general: 672].
        (Tatsuo Ishii)

        This is caused by the function waits for primary node which does not
        have pending data, while standbys have pending data.

          [pgpool-general: 672] Transaction never finishes
          http://www.pgpool.net/pipermail/pgpool-general/2012-June/000676.html

      - Fix wait_for_query_response() not to send param status to frontend if
        frontend is NULL. (Tatsuo Ishii)

        This could happen while processing reset_query_list and occur crash.

===============================================================================

                        3.0.7 (umiyameboshi) 2012/04/23

* Version 3.0.7

      This is a bugfix release against pgpool-II 3.0.6.

    __________________________________________________________________

* Bug fixes

      - Add m4 files. This should prevent compiling problem on older
        OS's. (Tatsuo Ishii)

      - Fix bug that the process exits before unlocking semaphore by a
        signal interrupt. (Tatsuo Ishii)

      - Fix a memory leak in case of reset_query. (Tatsuo Ishii)

      - Fix SimpleQuery() so that it restores parser memory context when:
         1) Builtin show commands are used
         2) Parallel query mode
         3) Query cache is used
       (Tatsuo Ishii)

      - Fix pool_ssl_read() to deal with large data reading. (Tatsuo Ishii)

        Original complain is here:
        http://www.pgpool.net/pipermail/pgpool-general/2012-March/000299.html

      - Fix hangup when PREPARE statement causes error. (Toshihiro Kitagawa)

        This issue was reported by Tomonari Katsumata:
        Subject: [pgpool-general: 121] question of pgpool's behavior

===============================================================================

                        3.0.6 (umiyameboshi) 2012/01/31

* Version 3.0.6

      This version fixes various bugs since 3.0.5.

      __________________________________________________________________

* Bug fixes

      - Fix infinite loop reported in this thread (Tatsuo Ishii):
        http://www.pgpool.net/pipermail/pgpool-general/2011-December/000099.html

        It was not considered the case that, when received buffer in primary was
        empty but the one in a standby was not, the standby spontaneously sent
        packet to pgpool.
        This could happen when, for example, reloading postgresql.conf.
        The fix is that such buffer in standby is discarded.

===============================================================================

                        3.0.5 (umiyameboshi) 2011/10/31

* Version 3.0.5

      This version fixes various bugs since 3.0.4.

      __________________________________________________________________

* Bug fixes

      - Fix bug with the handling of empty queries. The empty queries
        come to be handled the same as SELECT queries. This fix allows
        load-balance after the empty query(Toshihiro Kitagawa)

      - Fix insert_lock so that it works correctly even if the column
        definition such as "DEFAULT nextval(('"x_seq"'::text)::regclass)"
        (Toshihiro Kitagawa)

      - Fix log message which is emitted when pgpool-II cannot parse the
        query in the extended query protocol so that it shows the query
        (Toshihiro Kitagawa)

      - Fix description about backend_weight inpgpool-II manual. It can
        be changed by reloading pgpool.conf(Tatsuo Ishii)

      - Fix bug which does not update the node status when reattaching the
        node in raw mode(Guillaume Lelarge)

      - Fix bug that SELECTs which have subquery with FOR SHARE/UPDATE clause
        are sent to slave/standby(Tatsuo Ishii)

      - Fix bug which rewriting timestamp of default value fails in PREPARE
        statements. This used to work but was broken in 3.0(Toshihiro Kitagawa)

      - Fix crash of pgpool child when frontend connects if in raw mode,
        enable_hba is off and more than 2 backends(Toshihiro Kitagawa)

      - Fix some memory leaks(Toshihiro Kitagawa)

      __________________________________________________________________

* Enhancements

      - Allow time stamp rewriting to work with arbitrary expression in
        default value of a column. Before we detected anything including
        now() then simply replaced it to now(). This will lead to wrong
        rewriting of default value. for example, timezone('utc'::text, now()).
        Note that, however, this only adopts to simple queries. Extended
        protocols(for example Java, PHP PDO) or SQL "PREPARE" still remain
        same(Tatsuo Ishii)

      - Change error message "do_md5: read_password_packet failed" into debug
        level(Toshihiro Kitagawa)

===============================================================================

                        3.0.4 (umiyameboshi) 2011/06/01

* Version 3.0.4

      This version fixes various bugs since 3.0.3.

      __________________________________________________________________

* Incompatible changes

      - In streaming replication, if delay_threshold is 0 or health
        checking is disabled, the delay checking is not performed.
        This is the behaviour according to a description of the
        pgpool-II manual. But, so far the delay checking was performed
        even if health checking was disabled(Guillaume Lelarge)

      __________________________________________________________________

* Bug fixes

      - Fix pgpool-regclass() to be compiled in PostgreSQL 8.0 or later.
        7.4 still produces errors(Tatsuo Ishii)

      - Fix possible hangup when using /*NO LOAD BALANCE*/ comment in
        streaming replication(Toshihiro Kitagawa)

      - Fix hangup when received Flush(H) message or CloseComplete(C)
        message(Toshihiro Kitagawa)

      - Fix possible hangup that happen for the receiving timing of
        ReadyForQuery(Z) message after pgpool-II connects to backends(Toshihiro Kitagawa)

      - Add description about parameters for recovery_1st_stage_command
        and recovery_2nd_stage_command(Tatsuo Ishii)

      - Increase size of the internal system catalog cache from 32 to 128.
        This has the effect of reducing "unnamed prepared statement does
        not exist" error(Tatsuo, Kitagawa)

      - Fix bug with pcp_connect() which causes double free. Patch
        contributed by Jehan-Guillaume (ioguix) de Rorthais(Tatsuo Ishii)

      - Fix bug with start_recovery() which is apparently wrong usage of
        PQfinish()(Tatsuo Ishii)

      - Fix incorrect error message which is sent to the frontend when
        client idle time reached client_idle_limit(Tatsuo Ishii)

      - Fix "backend status" variable name correctly in pool_status.
        Replace the space with a '_'(Guillaume Lelarge)

      - Fix hangup when using md5 authentication method and running as
        daemon. Patch contributed by Nicolas Thauvin(Tatsuo Ishii)

      - Fix log_per_node_statement so that it prints statements in the
        extended query protocol. This used to work but was broken in 3.0
        (Toshihiro Kitagawa)

      __________________________________________________________________

* Enhancements

      - Add currval() and lastval() to black_function_list of sample
        configuration files. If they are load balanced, currval() or
        lastval() may be called before the result of nextval() or setval()
        is propagated to slaves(Tatsuo Ishii)

===============================================================================

                        3.0.3 (umiyameboshi) 2011/02/23

* Version 3.0.3

      This version fixes various bugs since 3.0.1. Please note that
      3.0.2 was canceled due to a packaging problem.

      __________________________________________________________________

* Incompatible changes

      - Now installing C function "pgpool_walrecrunning()" is recommended
          if you plan to use streaming replication mode.
          This is necessary for better use of online recovery in the mode.
        Also new variable "%P" can be used in the online recovery script.
        If you do not install the function, these functionalities cannot be
        used(Tatsuo Ishii).

      - In raw mode if there's only one DB node and if a problem arises
        with the DB node, it will be brought to down status. However if
        the DB node goes into good condition again, you can use the DB
        node without restarting pgpool. This change has been included in
        3.0, but did not work(Tatsuo, Kitagawa)

      __________________________________________________________________

* Bug fixes

      - Fix non portable code in password authentication.
        Bug report from a FreeBSD user(Tatsuo Ishii)

      - Fix bug that insert_lock locks all rows in user table
        (Tatsuo, Kitagawa)

      - Fix bug with password authentication. If user name is 32 bytes
        long, pgpool child segfaults.(Tatsuo Ishii)

      - Fix bug with md5 authentication. If raw mode or number of
        backend is 1, pgpool child segfaults. Patch contributed by
        Rob Shepherd(Tatsuo Ishii)

      - Fix long standing bug with timestamp rewriting against array
        and complex types. Patch contributed by Akio Ishida(Tatsuo Ishii)

      - Fix bug that debug_level directive doesn't work. Patch
        contributed by Gilles Darold(Tatsuo Ishii)

      - Fix possible crash of pgpool child while doing failover(Toshihiro Kitagawa)

      - Fix white/black_function_list so that it works correctly when user
        calls function with schema name(Tatsuo Ishii)

      - Fix bug that DROP DATABASE fails by connection cache(Toshihiro Kitagawa)

      - Fix bug that failover fails in raw mode(Toshihiro Kitagawa)

      - Fix possible termination of pgpool child when both simple query
        protocol and extended query protocol are used in one session
        (Toshihiro Kitagawa)

      - Fix possible hang up when an error occurs while using extended
        query protocol(Toshihiro Kitagawa)

      - Fix pgpool-regclass() so that it doesn't use PG_TRY/CATCH.
        It appeared that using PG_TRY/CATCH is not safe, sometimes backend
        dies with PANIC:  ERRORDATA_STACK_SIZE exceeded.(Tatsuo Ishii)

      - Fix bug that select query isn't sent to master node when it meets
        the following conditions(Toshihiro Kitagawa)
        - in MASTER/SLAVE mode
        - use extended query protocol
        - started transaction explicitly
        - after write queries

      - Fix bug with load_balance that JDBC driver sends BEGIN to master node
        many times(Toshihiro Kitagawa)

      - Fix pool_status so that failback_command and fail_over_on_backend_error
        show correct values(Toshihiro Kitagawa)

      - Remove parameters from pool_status: recovery_password,
        system_db_password(Toshihiro Kitagawa)

      - Fix online recovery problem in the streaming replication
        mode(Tatsuo Ishii). Consider following scenario. Suppose node 0 is
        the initial primary server and 1 is the initial standby
        server.

        1) Node 0 going down and node 1 promotes to new primary.
        2) Recover node 0 as new standby.
        3) pgpool-II assumes that node 0 is the new primary.

        This problem happens because pgpool-II regarded unconditionally
        the youngest node to be the primary. pgpool-II 3.0.3 now checks
        each node by using pgpool_walrecrunning() to see if it is a
        actually primary or not and is able to avoid the problem and
        regards node as standby correctly. Also you can use new
        variable "%P" to be used in the recovery script.  If you do
        not install the function, the above problem is not resolved.

      - Fix backend complaining "unexpected EOF on client connection"
        while doing failover in streaming replication mode(Tatsuo Ishii)

      - Fix pgpool crashes when all backends go down(Tatsuo Ishii)

      - Fix replication delay checking so that it does not keep persistent
        connection to backends. Because the persistent connection may
        become bogus if a node down and then wake up between replication
        delay checking period(Tatsuo Ishii)

      - Rewrite and review english document(Marc Cousin, Gleu)

      __________________________________________________________________

* Enhancements

      - Emit log if particular backend is down status while reading
        the status file(Tatsuo Ishii)

      - Emit error message if an error occurred by the query that
        pgpool executed(Tatsuo Ishii)

      - Add sql directories main Makefile(Tatsuo Ishii)

===============================================================================

                        3.0.1 (umiyameboshi) 2010/10/19

* Version 3.0.1

      This version fixes various bug in 3.0.

      __________________________________________________________________

* Bug fixes

      - Fix bug with md5 auth. If there's more than 1 servers to be
        authenticated, it segfaults(Tatsuo Ishii)

      - Fix bug that a child process crashes when clients execute a query
        contains syntax error in extended query protocol(Toshihiro Kitagawa)

      - Fix bug with handling of portal information, it terminates
        a child process(Toshihiro Kitagawa)

      - Fix hungup when a query sent to one node caused an error
        in extended query protocol(Toshihiro Kitagawa)

      - Fix typo in English doc. Patch contributed by Asaf Ohaion(Tatsuo Ishii)

===============================================================================

                        3.0 (umiyameboshi) 2010/09/10

* Version 3.0

      This is the first version of pgpool-II 3.0 series.
      That is, a "major version up" from 2.2 or 2.3 series.

      The biggest news is, this version adapts to PostgreSQL 9.0's new
      feature: Streaming Replication/Hot Standby. Streaming
      replication can be used as a sub mode of master slave
      mode. Master slave mode itself heavily enhanced:

      - SELECTs in explicit transactions can be load balanced

      - In extended protocol, PARSE/BIND/DESCRIBE messages are sent to
        the node which execute EXECUTE message, not all node. This
        will reduce lock contentions.

      - Auto start of transaction happens only when it needed.

      - Temporary tables can be used safely.

      - SELECT which calls functions possibly write to database
        executes on master(primary)

      Also many new features are added and major refactoring has been
      made to the internal structure of pgpool-II. For example, in
      replication mode, SELECTs calling functions possibly write to
      database will not allow to load balance.

      __________________________________________________________________

* New features

      - Online recovery can be used with master/slave/streaming
        replication mode(Tatsuo Ishii)

      - New directive "delay_threshold" is added to monitor
        replication delay in master/slave/streaming replication
        mode. If replication delay is too much, SELECTs are not load
        balanced(Tatsuo Ishii)

      - show pool_status shows replication delay in
        master/slave/streaming replication mode(Tatsuo Ishii)

      - New directive "log_standby_delay" is added to control logging of
        replication delay in master/slave/streaming replication
        mode(Tatsuo Ishii)

      - When insert_lock is enabled and the table includes SERIAL data
        type, issue row lock on the sequence table. Before we issues
        table lock. Problem is, the table lock conflicts with auto
        vacuum and sometimes caused excessive lock waiting(Tatsuo Ishii)

      - Add support for more "SHOW" commands: pool_nodes,
        pool_processes, pool_pools, and pool_version(Guillaume Lelarge)

      - Backend process id and whether frontend connects to this
        connection pool or not are added to pcp_proc_info's
        output(Tatsuo Ishii)

      - "Gracefully detach" option is added to pcp_detach_node. With
        this option, pcp_detach_node waits until all frontends
        disconnected(Tatsuo Ishii)

      - New directive "white_function_list" and "black_function_list"
        are added to register functions those do not or do write to
        database(Tatsuo Ishii)

      - In master/slave mode, SELECTs to system catalogs executes only
        on master/primary(Tatsuo Ishii)

      - In master/slave mode, SELECTs to temporary table executes only
        on master/primary(Tatsuo Ishii)

      - In master/slave mode, write queries outside of explicit
        transactions no longer trigger to start internal
        transaction(Tatsuo Ishii)

      - In master/slave mode, SELECTs inside explicit transactions are
        load balanced(Tatsuo, Kitagawa)

      - In master/slave mode, commands are no longer sent to all DB
        nodes. This will prevent unnecessary locking(Tatsuo, Kitagawa)

      - New command option adds to ignore the status file when
        starting up(Tatsuo Ishii)

      - Supports PostgreSQL 9.0's new VACUUM syntax(Tatsuo Ishii)

      - New directive "failover_if_affected_tuples_mismatch" controls
        the behavior when number of result rows of
        INSERT/UPDATE/DELETE are differ(Tatsuo Ishii)

      - When number of result rows of INSERT/UPDATE/DELETE are
        differ, each number are logged(Tatsuo Ishii)

      - md5 authentication is supported in replication mode and
        master/slave mode(Tatsuo Ishii)

      - Allow to force to move to online recovery second stage even
        there are connecting frontends(Tatsuo Ishii)

      - If there's only one DB node and it triggers failover,
        pgpool-II will automatically connects if the DB node coming
        up(Tatsuo Ishii)

      - Pcp commands supports long options(Guillaume Lelarge)

      - New directive "debug_level" added to control the debug message
        logging(Tatsuo Ishii)

      - Allow to use various boolean representations as PostgreSQL in
        pgpool.conf(Toshihiro Kitagawa)

      - New C language function pgpool_switch_xlog for online recovery
        added(Toshihiro Kitagawa)

      - New C language function pgpool_regclass added to avoid a trouble
        about handling of duplicate table names in different schema(Tatsuo Ishii)

      __________________________________________________________________

* Bug fixes

      - Do not rewrite statement which accesses columns having now()
        etc. as the default value but the data type are not timestamp
        etc.  Otherwise we have an error in DMLs(Tatsuo Ishii)

      - Fix timestamp rewriting not to omit schema qualification(Tatsuo Ishii)

      - Fix bug with timeout handling in pcp commands(Tatsuo Ishii)

      - Fix SSL hang when large amount of data transferred(Tatsuo Ishii)

      - Fix failover when there's only one DB node(Tatsuo Ishii)

      - Fix bug with postmaster start check in online recovery.
        Before it continued infinitely to try to connect to postmaster
        if the first attempt failed(Tatsuo Ishii)


===============================================================================
2.3 Series (2009/12/07 - 2012/08/06)
===============================================================================

                    2.3.4 (tomiteboshi) 2012/08/06

* Version 2.3.4

      This version fixes various bugs since 2.3.3.

      __________________________________________________________________

* Bug fixes

    - Fix do_error_execute_command() so that it discards responses from
      backend until ErrorResponse received. (Toshihiro Kitagawa)

      Note that we need to preserve non-error responses (i.e. ReadyForQuery)
      and put back them using pool_unread().
      Otherwise, ReadyForQuery response of DEALLOCATE. This could happen if
      PHP PDO used.

    - Fix SimpleForwardToFrontend() so that it reset select_in_transaction
      flag and execute_select flag when bind error occurred while executing
      SELECT. (Toshihiro Kitagawa)

    - Fix SSL connection sometimes hung if lots of data read from backend.
      This is caused by the buffering in OpenSSL layer. To fix the problem,
      (Tatsuo Ishii)

      we check the buffer has any pending data by using SSL_pending() before
      calling select(2).
      See thread [Pgpool-general] Fwd: PGPOOL II 2.3.3 hang in ssl mode for
      more details.

    - Fix bug with pcp_check_fd()'s timeout handling. (Tatsuo Ishii)

      Per erboles.
        Subject: [Pgpool-general] question about pcp_check_fd
        Date: Sun, 23 May 2010 18:21:41 -0500
        To: pgpool <pgpool-general@pgfoundry.org>

    - Do not force replication of DEALLOCATE if operated in master/slave mode.
      Reported by Jan Kantert. (Toshihiro Kitagawa)

      See:
        Subject: [Pgpool-hackers] Problems with PgPool 2.3.3 Prepare /
                 Deallocation handling in Master/Slave mode
        Date: Fri, 28 May 2010 20:59:47 +0200
      For more details.

    - Make timestamp rewriting schema aware. (Tatsuo Ishii)

    - Do not rewrite statement which accesses columns having now() etc. as the
      default value but the data type are not timestamp etc. (Tatsuo Ishii)

      Otherwise we have an error in DMLS. See:
        Subject: [Pgpool-general] function epoch seems to be causing error
        To: pgpool-general@pgfoundry.org
        Date: Mon, 16 Aug 2010 21:48:31 +0000 (UTC)
      For more details.

    - Fix insert_lock to be schema aware. (Tatsuo Ishii)

    - Fix long standing bug with timestamp rewriting against array and complex
      types.  (Tatsuo Ishii)


      Failed examples are:

        INSERT INTO r1(col[1], col2.foo) VALUES (1, 2); -- insert_column_item
        UPDATE r1 SET col1[1] = 1, col2.foo = 1; -- set_target
        PREPARE "p" (int4[]) AS  SELECT $1[1]; -- c_expr
        SELECT (ARRAY[1,2,3])[1];
        SELECT (ARRAY[ARRAY[1]])[1][1];
        SELECT ('{1,2,3}'::int[])[1];
        SELECT ('{1,2,3}'::int[3])[1];
        SELECT r1.col[1], (r1.col1).bar, (r1.col1).* FROM r1; -- columnref
        SELECT (r1.col1).baz[1], (r1.col1).baz[1][2] FROM r1;

      Patch provided by Akio Ishida.

    - Fix buffer overrun problem when pcp password is longer than 32.
      (Tatsuo Ishii)

    - Fix wait_for_query_response() not to send param status to frontend if
      frontend is NULL. This could happen while processing reset_query_list.
      (Tatsuo Ishii)

===============================================================================

                        2.3.3 (tomiteboshi) 2010/04/23

* Version 2.3.3

      This version fixes various bugs since 2.3.2.2.

      __________________________________________________________________

* Incompatible changes

      - Please note that this version of pgpool consumes more shared
        memory than before. If you encounter problems when starting up
        pgpool, please look into pgpool log. If you find messages
        something like "could not create shared memory segment: Cannot
        allocate memory", please increase the shared memory on your
        system.

      - Now parallel mode requires replication mode turned
        on. parallel mode without replication mode turned on has been
        broken since pgpool-II was born anyway(Toshihiro Kitagawa)

      - Change default value for insert_lock to false since there's no
        point in turning this on in master/slave mode. Fix suggested by
        Fujii Masao(Tatsuo Ishii)

      __________________________________________________________________

* Newly added documents

      - README.online-recovery, which is an internal document of
        online recovery, added(Tatsuo Ishii)

      __________________________________________________________________

* Bug fixes

      - Fix long standing bug since pgpool-II 1.0 which causes
        segfault of pgpool child process.  This was caused by
        miscalculation of shmem size in pgpool parent. Bug analysis by
        Kitagawa patch created by Tatsuo

      - Add restriction for parallel mode(Toshihiro Kitagawa)
        - The Natural Join is not supported
        - The USING CLAUSE is converted to ON CLAUSE by query rewrite
          process

      - Fix possible crash during rewriting JOIN syntax that have
        USING in parallel query mode(Toshihiro Kitagawa)

        This fix is supporting such as following JOIN syntax.

         example:
         - SELECT * FROM a JOIN b USING (aid) JOIN c USING (cid);
         - SELECT * FROM a JOIN b USING (aid) JOIN c USING (cid)
           JOIN d USING (did)

      - Fix parallel query so that it can parse INSERT statements that
        have current_time before a partitioning key column
        (Toshihiro Kitagawa)

      - Fix SimpleForwardToBackend() so that pgpool doesn't keep
        waiting for reply from a backend, when clients using the
        extended query protocol cause a command error such as bind
        error. This bug occur in master/slave, raw, and connection
        pool mode.  This fix is, sending SYNC message to recover error
        after command error(Toshihiro Kitagawa)

      - Fix SIGINT/SIGQUIT is ignored if pgpool child is in
        select(). In this case pgpool retries select() thus the signal
        is ignored(Tatsuo Ishii)

      - Fix connect_inet_domain_socket_by_port/
        connect_unix_domain_socket_by_port so that they check if
        SIGTERM/SIGINT/SIGQUIT signal has been delivered.  Per bug
        report from Daniel Codina(Tatsuo Ishii)

      - Fix possible crash during creating "kind mismatch" error
        message. This used to work but was broken in 2.3.2(Tatsuo Ishii)

      - Fix bug with health checking. If a network problem such as
        unplugged wire happens while calling connect(), health
        checking does not work since
        connect_unix_domain_socket()/connect_inet_domain_socket() do
        retry if connect() is interrupted by ALARM signal. Added new
        retry argument which controls the retrying behavior to those
        functions.  Per bug report and problem analysis by Daniel
        Codina(Tatsuo Ishii)

      - Fix enbug in 2.3.2.2 with time stamp rewriting in
        SimpleForwardToBackend. Per bug report from Bugtrack #1010771.
        Report from Peter Pramberge(Tatsuo Ishii)

      - Fix rewriting "*" in parallel query.  Patch contributed by
        sho-san(Toshihiro Kitagawa)

      - Fix connect_inet_domain_socket_by_port() so that it print out
        error message by using hstrerror(), rather than
        strerror()(Tatsuo Ishii)

===============================================================================

                    2.3.2.2 (tomiteboshi) 2010/02/22

* Version 2.3.2.2

      This version fixes various bug in 2.3.x.

      - When rewriting timestamp in extended query, it allocated less
        than what it actually needed. This causes random problematic
        behavior, typically "message: invalid string in message" error
        in backend(Tatsuo Ishii).

      - In extended query, if one of parameters contains NULL, ppool
        crashes(Tatsuo Ishii).

      - If in previous status file all nodes were marked down status,
        it is regarded that this file is bogus. This will prevent "all
        node down" syndrome(Tatsuo Ishii).

===============================================================================

                    2.3.2.1 (tomiteboshi) 2010/02/11

* Version 2.3.2.1

      This version fixes bug in 2.3.x. It is identified that
      pgpool-II 2.3.x has a problem with erroneous query
      processing(Akio Ishida).

===============================================================================

                    2.3.2 (tomiteboshi) 2010/02/07

* Version 2.3.2

      This version includes various fixes for bugs in 2.3.1 or before.
      All 2.3.x users are encouraged to upgrade to 2.3.2 as soon as
      possible.

      Also this version enables long awaited SSL support and large
      object replication support.

      __________________________________________________________________

* Enhancements

      - SSL support(Sean Finney)

      - Large object replication support. You need PostgreSQL 8.1 or
        later, however(Tatsuo Ishii)

      - Emit statement log when error or notice message comes from
        query parsing process. This is useful because PostgreSQL does
        not log particular statement if the error was detected
        *before* raw parser get executed.  This typically happens
        when encoding error was found(Tatsuo Ishii)

      - Display original query to log if kind mismatch error was
        caused by DEALLOCATE(Tatsuo Ishii)

      - While health checking and recovery use postgres database if
        possible.  If postgres database does not exist, use template1
        as it stands now.  While connecting template1, certain
        commands, for example DROP DATABASE cannot used. Using postgres
        database allows to use these commands while recovery(Tatsuo Ishii)

      __________________________________________________________________

* Bug fixes

      - Fix errors in timestamp rewriting which occasionally cause
        broken packet sentto slave nodes(Tatsuo Ishii)

      - Fix errors when timestamp rewriting is used with V2
        protocol(Toshihiro Kitagawa)

      - Propagate Bind, Describe and Close messages to only master
        node if running in master/slave and in transaction (Tatsuo Ishii)

      - Fix do_child() so that check_stop_request() exits immediately
        when smart shutdown signal has been sent.  This has been used
        to work in 2.2(Toshihiro Kitagawa)

      - Fix ProcessFrontendResponse not to accept invalid frontend
        packet(Xavier Noguer)

      - Use %dz for sizeof in fprintf for more portability(Tatsuo Ishii)

      - Fix compiler warnings(Tatsuo Ishii)

      - Do not force replication of DEALLOCATE if operated in
        master/slave mode. Now that pgpool do not execute PARSE in all
        nodes, this was pointless and caused problem (kind mismatch
        when executing DEALLOCATE)(Tatsuo Ishii)

===============================================================================

                        2.3.1 (tomiteboshi) 2009/12/18

* Version 2.3.1

      This version includes various fixes for bugs in 2.3 or before.
      All 2.3 users are encouraged to upgrade to 2.3.1 as soon as
      possible.
      __________________________________________________________________

* Bug fixes

      - If all of following conditions met, incorrect data is written
        to DB(Tatsuo Ishii)

        - pgpool is running in replication mode
        - pgpool is running on 64bit OS
        - INSERT or UPDATE are used which explicitly include now(),
        - CURRENT_TIMESTAMP, CURRENT_DATE, CURRENT_TIME. Or the target
        - Table's default value use above functions
        - The SQL statement includes out of 32bit
          integer value(-2147483648 to 2147483647 in decimal)

        Example SQL: INSERT INTO t1(id, regdate) VALUES(98887776655,
        NOW());

      - Fix crush in case of more than 18 DB nodes are used(Tatsuo Ishii)

      - Enhance kind mismatch error message. If kind is ERROR or
        NOTICE, the error or notice message from PostgreSQL will be printed
        (Tatsuo Ishii)

===============================================================================

                            2.3 (tomiteboshi) 2009/12/07

* Version 2.3

      This version enhances replication, especially CURRENT_TIMESTAMP,
      CURRENT_DATE, now() etc. now can be properly replicated. Also
      performance of replication when num_init_children == 1 is
      enhanced. Pgpool-II now records the status of down nodes, and
      remember when it restarts to ensure that keep the node status as
      before. Also some logs are enhanced and more fine fail over
      controls are added. Please note that pgpool-II 2.3 includes all
      of enhancements and fixes of pgpool-II 2.2.1 to 2.2.6.

      __________________________________________________________________

* Incompatibilities from 2.2.x

      - pgpool_status file is created under logdir. So you need to
        give write permission to the directory so that pgpool-II can
        read/write pgpool_status file.

      __________________________________________________________________

* Enhancements

      - Enable proper replication of results of temporal functions
        (CURRENT_TIMESTAMP, CURRENT_DATE, now() etc.). Now
        applications can execute INSERT/UPDATE tables which include
        default values using those temporal functions. There are small
        limitations. See restriction sections of docs for more
        details (Akio Ishida)

      - Use PostgreSQL 8.4's SQL parser(Akio Ishida)

      - Enhance the performance 20% to 100% of replication when
        num_init_children == 1(Tatsuo Ishii)

      - Add new directive log_per_node_statement which is similar to
        log_statement except that prints info for each DB node to make
        it easier which query is sent to which DB node(Tatsuo Ishii)

      - Add new directive fail_over_on_backend_error to control the
         behavior of fail over(Tatsuo Ishii)

      - Record DB node status and remember when pgpool-II restarts(Tatsuo Ishii)

      - EXPLAIN and EXPLAIN ANALYZE for SELECT query are now load
        balanced. This will prevent unwanted kind mismatch errors when
        EXPLAIN produces slightly different plan(Tatsuo Ishii)

      - Enhance CSS of pgpool-ja.html(Tatsuo Ishii)

      - Add sample configuration file for replication mode and
        master/slave mode(Tatsuo Ishii)

     - Add test for temporal data(Akio Ishida)


===============================================================================
2.2 Series (2009/02/08 - 2012/08/06)
===============================================================================

                    2.2.8 (urukiboshi) 2012/08/06

* Version 2.2.8

      It includes various fixes for bugs various bug fixes in 2.2.7.

      __________________________________________________________________

* Bug fixes

      - Fix do_error_execute_command() so that it discards responses from
        backend until ErrorResponse received. (Toshihiro Kitagawa)

        Note that we need to preserve non-error responses (i.e. ReadyForQuery)
        and put back them using pool_unread().
        Otherwise, ReadyForQuery response of DEALLOCATE. This could happen if
        PHP PDO used.

      - Fix SimpleForwardToFrontend() so that it reset select_in_transaction
        flag and execute_select flag when bind error occurred while executing
        SELECT. (Toshihiro Kitagawa)

      - Fix bug with pcp_check_fd()'s timeout handling. (Tatsuo Ishii)

        Per erboles.
          Subject: [Pgpool-general] question about pcp_check_fd
          Date: Sun, 23 May 2010 18:21:41 -0500
          To: pgpool <pgpool-general@pgfoundry.org>

      - Fix buffer overrun problem when pcp password is longer than 32.
        (Tatsuo Ishii)

      - Fix wait_for_query_response() not to send param status to frontend if
        frontend is NULL. This could happen while processing reset_query_list.
        (Tatsuo Ishii)

===============================================================================

                    2.2.7 (urukiboshi) 2010/04/15

* Version 2.2.7

      This version enhances displaying error messages when kind
      mismatch error occurs. Also it includes various fixes for bugs
      in 2.2.6 or before as usual.

      __________________________________________________________________

* Bug fixes

      - Fix occasional hangup in extend protocol + master/slave mode,
        row mode or connection pool mode. Back patch from 2.3
        tree(Toshihiro Kitagawa)

      - Fix long standing bug since pgpool-II 1.0 which causes
        segfault of pgpool child process. This was caused by
        miscalculation of shmem size in pgpool parent. Bug analysis by
        Kitagawa patch created by Tatsuo

      - Send Parse, Bind, Describe and Close message to only master
        node if operated in explicit transaction and master/slave
        mode(Tatsuo Ishii).

      - Emit a log when postmaster goes down(Tatsuo Ishii)

      - Fix memory leak in make_persistent_db_connection(Xavier
        Noguer)

      - Do not force replication of DEALLOCATE if operated in
        master/slave mode. Now that pgpool do not execute PARSE in all
        nodes, this was pointless and caused problem (kind mismatch
        when executing DEALLOCATE) (Tatsuo Ishii)

      - Fix crash with show pool_status when there many (more than 18)
        DB nodes(Tatsuo Ishii)

      - Enhance "kind mismatch" message. If kind is ERROR or NOTICE,
        print the ERROR/NOTICE message to help users to find what's
        going on(Tatsuo Ishii)

===============================================================================

                        2.2.6 (urukiboshi) 2009/12/01

* Version 2.2.6

      This version enhances handling of backend weight. Also it allows
      to use temp tables in master/slave mode. It includes various
      fixes for bugs in 2.2.5 or before as usual.

      __________________________________________________________________

* Bug fixes

      - Do not allow to load balance DECLARE, CLOSE, FETCH and
        MOVE. If data gets updated and CLOSE issued after transaction
        commit(i.e. holdbale cursor), this will cause data
        inconsistency since CLOSE is executed one of the severs,
        rather than all(Tatsuo Ishii)

      - In master/slave mode, execute Parse message on only master
        node. In previous versions Parse executed on all nodes, which
        grabbed unnecessary lock(Tatsuo Ishii)

      - Remove init script from all runlevels before uninstall(Devrim)

      - Fix pgpool.spec(Devrim)

      - Do not execute REINDEX DATABASE or SYSTEM, CREATE/DROP TABLE
        SPACE inside a transaction block(Tatsuo Ishii)

      __________________________________________________________________

* Enhancements

      - Allow to change weight by reloading pgpool.conf. This will take
        effect for next client sessions(Tatsuo Ishii)

      - Reply with useful error messages, rather than "server closed
        the connection unexpectedly" when authentication fails(Glyn
        Astill)

      - Add info to logs when writing to sockets fails to know if it
        was for backend or frontend(Tatsuo Ishii)

      - Do not complain when writing to socket of frontend
        fails(Tatsuo Ishii)

      - Allow to use temp tables in master/slave
        mode. INSERT/UPDATE/DELETE will automatically be sent to
        master only. Still SELECT you need to add /*NO LOAD BALANCE*/
        comment(Tatsuo Ishii)

      - Add temp table test to test/jdbc(Tatsuo Ishii)

===============================================================================

                        2.2.5 (urukiboshi) 2009/10/4

* Version 2.2.5

      This version fixes various bugs in 2.2.4 or before.

      __________________________________________________________________

* Bug fixes

      - Fix connection_count_down(). It decrements the connection
        counter too much in some corner cases and causes online
        recover never completes(Tatsuo Ishii)

      - Detect frontend exiting while waiting for commands complete in
        other cases such as internal locks are issued and Parse
        (Tatsuo Ishii)

      - Fix infinite loop in reset_backend(Xavier Noguer, Tatsuo)

      - Fix Parse() to print actual query when it detects kind
        mismatch error(Tatsuo Ishii)

      - Document enhancements(Tatsuo Ishii)

===============================================================================

                        2.2.4 (urukiboshi) 2009/8/24

* Version 2.2.4

      This version fixes various bugs in 2.2.3 or before.

      __________________________________________________________________

* Bug fixes

      - Fix possible bug introduced in pgpool-II 2.2.2.  Load balance
        control variables may remain not be restored and subsequent
        DML/DDL call might sent to only master node(Tatsuo Ishii)

      - Send NOTICE message to frontend periodically if V2 protocol is
        used. This is ifdef out since it affects visible change to
        applications.  2.2.3 unconditionally sends param packet to
        client even it uses version 2 protocol, which is apparently
        wrong. Also tweak checking period from 1 second to 30 seconds
        since 1 second seems too aggressive(Tatsuo Ishii)

      - Block signals before forking children rather after.  Otherwise
        parent will be killed by failover signal if it receives a
        signal before establishing signal handler(Tatsuo Ishii)

      - Remove unnecessary spaces and tabs at the end of line(Jun Kuriyama)

===============================================================================

                            2.2.3 (urukiboshi) 2009/8/11

* Version 2.2.3

      This version fixes various bugs in 2.2.2 or before.

      __________________________________________________________________

* Bug fixes

      - Fix child process death if one of backends is not available(Tatsuo Ishii).

      - Fix various parallel query bugs(Yoshiharu Mori)

      - Fix message corruption for kid mismatch error(Akio Ishida)

      - Now statement_time works(Tatsuo Ishii)

      - Enhance health checking to detect postmaster stopping by
        SIGSTOP(Tatsuo Ishii)

      - Detect frontend abnormal exiting while waiting for reply from
        backend. This only works with V3 protocol(Tatsuo Ishii)

      - Do not start internal transaction if command is CLUSTER
        without arguments(Tatsuo Ishii)

      - Fix bug with COPY FROM in that backend process remains after
        COPY failed(Tatsuo Ishii)

      __________________________________________________________________

* Enhancements

      - Show last query for extended protocol(Akio Ishida)

      - Allow to compile sql/pgpool-recovery/pgpool-recovery.c with
        PostgreSQL 8.4(Tatsuo Ishii)

===============================================================================

                        2.2.2 (urukiboshi) 2009/5/5

* Version 2.2.2

      This version fixes various bugs in 2.2.1 or before. Please note
      that an important fix is made to avoid data inconsistency risk,
      which could happen when client does not exit gracefully(without
      sending "X" packet) while pgpool is trying to send data to
      it. This could happen with all version of pgpool-II.

      __________________________________________________________________

* Bug fixes

      - Ignore write error on frontend connection. This is needed to
        continue processing with backend, otherwise we risk data
        inconsistency(Tatsuo Ishii)

      - Fix bug introduced in 2.2.1 (In master slave mode, sometimes
          DEALLOCATE fails). If prepared statement reused, pgpool
          hangs(Toshihiro Kitagawa)

      - Fix pgpool crash when SQL command PREPARE and protocol level
        EXECUTE are mixed. The bug was introduced in 2.2(Tatsuo Ishii)

      - Avoid "unexpected EOF on client connection" error in PostgreSQL
        when reset query fails(Tatsuo Ishii)

===============================================================================

                        2.2.1 (urukiboshi) 2009/4/25

* Version 2.2.1

      This version fixes various bugs in 2.2.

      __________________________________________________________________

* Bug fixes

      - In master slave mode, sometimes DEALLOCATE fails. This is
        caused by that the first PREPARE was not executed on the
        slave(Toshihiro Kitagawa)

      - Update pgpool.spec along with related files(Devrim)

      - Fix insert_lock so that it is ignored when protocol version is
        2(Tatsuo Ishii)

      - Remove excessive log messages regarding parameter change notice(Tatsuo Ishii)

      - Add missing files to doc(Tatsuo Ishii)

===============================================================================

                            2.2 (urukiboshi) 2009/2/28

* Version 2.2

      This version enhances SERIAL data type handling and on line
      recovery. Also an important bug, serializable transactions could
      cause data inconsistency among DB nodes, is fixed. Query
      cancelation, which never worked since pgpool-II was born, is
      finally fixed.

      __________________________________________________________________

* New features/enhancements

        - With insert_lock, now a table is locked only if it has
          SERIAL data type and now the default value for insert_lock
          is true(Tatsuo Ishii)

        - Start internal transaction other than INSERT, UPDATE, DELETE
          and SELECT to keep node consistency(Tatsuo Ishii)

        - Add client_idle_limit_in_recovery directive. This will
          prevent 2nd stage of on line recovery from not going forward
          by idle clients sitting forever(Tatsuo Ishii)

        - Add pid_file_name directive which specifies a path to the
          file containing pgpool process id. "logdir" is no more used(Tatsuo Ishii)

        - Allow to load balance DECLARE, FETCH and CLOSE(Tatsuo Ishii)

        - Add -d option to pcp commands(Jun Kuriyama)

        - Enhance kind mismatch error message to include original
          query string(Tatsuo Ishii)

      __________________________________________________________________

* Bug fixes

        - Close all file descriptors when running in daemon mode.
          Otherwise we inherit sockets from apache when it's
          started by pgpoolAdmin. This results in that port 80 is
          occupied for example.  Patch provided by Akio
          Ishida. Also add chdir("/"). This is always good for
          daemon programs(Tatsuo Ishii)

        - Allow MD5 authentication in raw mode as stated in docs(Tatsuo Ishii)

        - Check transaction serialization failure error in
          serializable mode and abort all nodes if so. Otherwise
          we allow data inconsistency among DB nodes(Tatsuo Ishii).

          See following scenario: (M:master, S:slave)

            M:S1:BEGIN;
            M:S2:BEGIN;
            S:S1:BEGIN;
            S:S2:BEGIN;
            M:S1:SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
            M:S2:SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
            S:S1:SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
            S:S2:SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
            M:S1:UPDATE t1 SET i = i + 1;
            S:S1:UPDATE t1 SET i = i + 1;
            M:S2:UPDATE t1 SET i = i + 1; <-- blocked
            S:S1:COMMIT;
            M:S1:COMMIT;
            M:S2:ERROR:  could not serialize access due to concurrent update
            S:S2:UPDATE t1 SET i = i + 1; <-- success in UPDATE and data
                                              becomes inconsistent!

        - avoid kind mismatch error caused by "SET TRANSACTION
          ISOLATION LEVEL must be called before any query"(Tatsuo Ishii).

           This could happen in following scenario:

            M:S1:BEGIN;
            S:S1:BEGIN;
            M:S1:SELECT 1; <-- only sent to MASTER
            M:S1:SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
            S:S1:SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
            M: <-- error
            S: <-- ok since no previous SELECT is sent. kind mismatch error occurs!

        - Process status display has extra space on FreeBSD(Jun Kuriyama)

        - Fix incorrect kind mismatch detection case. e.g: BEGIN;
          BEGIN; (Tatsuo Ishii)

        - If PostgreSQL sends lots of DEBUG message, sometimes pgpool
          complains:
          2008-11-08 22:41:53 ERROR: pid 23744: do_command: backend does not
          return ReadyForQuery. This due to a wrong assumption for the
          client/server protocol(Tatsuo Ishii)

        - Fix the case when sending an erroneous query to abort
          transaction. It assumed that after sending an error query,
          always ReadyForQuery came right after that. If some
          debugging or logging verboseness is set, PostgreSQL might
          sends NOTICE before ReadyForQuery(Tatsuo Ishii)

        - Query cancelation now works. It never worked since pgpool-II
          was born(Tatsuo Ishii)

        - Fix online recovery to wait for failback done before
          allowing to accept connections from clients. It was supposed
          to work like this but actually was not since the day 0 when
          online recovery was born. Without the fix there could be
          potential data inconsistency among DB nodes(Tatsuo Ishii)

        - Fix pgpool-II crash after on line recovery. This happens
          after the failback process adds a recovered node which has
          no connection to the node(Tatsuo Ishii)

        - Fix pgpool-II errors when postgresql.conf is reloaded. This
          was caused by parameter status packet sent asynchronously
          from backend, which indicates the internal setting of
          backend has been changed(Tatsuo Ishii)

      __________________________________________________________________

* Incompatible changes

        - Always fail over and restart all children. Before we do
          restart only if master has not been changed. This is
          wrong. If we have trouble with network cable or something,
          TCP/IP stack keeps on retrying for long time and the only
          way to prevent it is restarting process(Tatsuo Ishii)

        - "logdir" is no more used. Instead use
          "pid_file_name"(Tatsuo Ishii)

        - Default value for insert_lock is now true(Tatsuo Ishii)


===============================================================================
2.1 Series (2008/07/25 - 2008/07/25)
===============================================================================

                            2.1 (inamiboshi) 2008/7/25

* Version 2.1

      __________________________________________________________________

* New feature

        - Add '%m' format to failover_command and failback_command to
          obtain new master node ID. (Yoshiyuki Asaba)
        - Add '%m' format to failover_command and failback_command to
          obtain old master node ID. (Yoshiyuki Asaba)
        - Add new directive "recovery_timeout" to specify recovery
          timeout in second. (Taiki Yamaguchi)
        - Add optino '-v' to print pgpool version. (Yoshiyuki Asaba)

      __________________________________________________________________

* Incompatibility

        - Restrict pgpool_recovery() and pgpool_remote_start()
          functions to superusers. (Yoshiyuki Asaba)
        - Do not create a connection pool to standby node in raw
          mode. (Yoshiyuki Asaba)
        - Remove "replication_timeout" parameter. (Yoshiyuki Asaba)
          - This enabled if replication_strict was false. However,
            replication_strict was already removed.
        - Ignore timeout argument of pcp commands. (Taiki Yamaguchi)
        - Do not replicate "COPY TO STDOUT" when replicate_select is
          false. (Yoshiyuki Asaba)

      __________________________________________________________________

* Bug fix

    ** General

        - Fix crash when CloseComplete message was
          received. (Yoshiyuki Asaba)
        - Improve network I/O routine. (Yoshiyuki Asaba)
        - Fix compile errors on Solaris 10. (Yoshiyuki Asaba)
        - Improve log messages of health check and recovery. (Tatsuo Ishii)
        - Change error level of the "failed to read kind from
          frontend" message from ERROR to LOG. (Yoshiyuki Asaba)
        - Fix failover failure in raw mode. (Taiki Yamaguchi)
        - Fix zombie process bug. (Yoshiyuki Asaba)
        - Fix health_check_timeout to work correctly. (Kenichi Sawada)
        - Support ps status on FreeBSD. (ISHIDA Akio)
        - Improve bind(2) failure report. (Jun Kuriyama)
        - Improve error message when client authentication
          failed. (Tatsuo Ishii)

    ** Replication

        - Fix replicate_select to work correctly. (Tatsuo Ishii)
        - Fix a wrong rollback bug with extended query. (Yoshiyuki Asaba)
        - Fix a bug with asynchronous query. (Yoshiyuki Asaba)
        - Fix hint clause handling like /*REPLICATION*/ with extended
          query. (Yoshiyuki Asaba)
        - Fix crash of "DEALLOCATE ALL". (Yoshiyuki Asaba)
        - Fix hang up when a backend node does immediate
          shutdown. (Yoshiyuki Asaba)
        - Fix hang up online recovery in high load. (Yoshiyuki Asaba)
        - Fix hang up with extended query protocol when SELECT is
          failed inside a transaction block. (Yoshiyuki Asaba)

    ** Master Slave

        - Fix load balancing to work correctly. (Yoshiyuki Asaba)
        - Fix crash if SET, PREPARE or DEALLOCATE is executed inside a
          transaction block. (Yoshiyuki Asaba)

    ** Parallel query

        - Fix INSERT failure. (Yoshiharu Mori)
        - Fix syntax error when a query contains "AS" in FROM
          clause. (sho)
        - Fix Hung up when two or more statement was executed
          in parallel mode (Yoshiharu Mori)
        - Fix Query rewriting of Join Expression and DISTINCT ON
          (Yoshiharu Mori)

===============================================================================
2.0 Series (2007/11/16 - 2007/11/21)
===============================================================================

                    2.0.1 (hikitsuboshi) 2007/11/21

      * Version 2.0.1
      * Fix process down with UPDATE or DELETE query.(Yoshiyuki Asaba)
      * Send a syntax query only to a master node if master_slave is
        true.(Yoshiyuki Asaba)

===============================================================================

                    2.0 (hikitsuboshi) 2007/11/16

* Version 2.0

      __________________________________________________________________

* Incompatibility since pgpool-II 1.x

        - the default value for ignore_leading_white_space is now
          true(Yoshiyuki Asaba)
        - replicate_strict is removed. The value is always
          true(Yoshiyuki Asaba)

      __________________________________________________________________

* General
        - Allow to reload pgpool.conf(Yoshiyuki Asaba)
        - The parser is now compatible with PostgreSQL 8.3(Yoshiyuki Asaba)
        - Add new directive "failover_command" to specify command when
          a node is detached(Yoshiyuki Asaba)
        - Add new directive "client_idle_limit" to specify the time out since
          the last command is arrived from a client(Tatsuo Ishii)

      __________________________________________________________________

* Replication

        - Always start a new transaction even if the query is not in
          an explicit transaction to enhance the reliability of
          replication(Yoshiyuki Asaba)
        - Enhance the performance of replication for write
          queries. Now the worst case is 1/2 compared with single DB
          node regardless the number of DB nodes. Previous release
          tends to degrade according to the number of DB
          nodes(Yoshiyuki Asaba)
        - Add "online recovery" which allows to add a DB node and sync
          with other DB nodes without stopping the pgpool
          server(Yoshiyuki Asaba)
        - Abort a transaction if INSERT, UPDATE and DELETE reports
          different number of result rows(Yoshiyuki Asaba)

          x=# update t set a = a + 1;
          ERROR:  pgpool detected difference of the number of update tuples
          HINT:  check data consistency between master and other db node

        - If the results from DB nodes do not match, select the
          possible correct result by "decide by majority". Previous
          release always trust the result of the master DB
          node(Yoshiyuki Asaba)
        - Allow load balance in V2 frontend/backend protocol(Yoshiyuki Asaba)

      __________________________________________________________________

* Parallel query

        - Allow "partial replication" to enhance the performance of
          the parallel query(Yoshiharu Mori)


===============================================================================
1.3 Series (2007/10/23 - 2007/10/23)
===============================================================================

                        1.3 (sohiboshi) 2007/10/23

      * Version 1.3
      * Add new "authentication_timeout" directive, being the default
        value is 60. (Yoshiyuki Asaba)
        - Maximum time in seconds to complete client authentication.
      * Reject a connection when startup packet length is greater than
        10,000 byte. (Yoshiyuki Asaba)
      * Fix invalid memory access when pgpool processed DEALLOCATE
        statement. (Yoshiyuki Asaba)
      * Fix hang up in load balance mode. (Yoshiyuki Asaba)
        - This was introduced in V1.2.
      * Fix segmentation fault in 64-bit environment when query cache
        is enable. (Yoshiyuki Asaba)


===============================================================================
1.2 Series (2007/08/01 - 2007/09/28)
===============================================================================

                        1.2.1 (tomoboshi) 2007/09/28

      * Version 1.2.1
      * Fix deadlock while processing Parse message. (Yoshiyuki Asaba)
      * Fix memory leak in reset_prepared_list(). (Yoshiyuki Asaba)
      * Fix compile error on FreeBSD 4.11. (Yoshiyuki Asaba)
      * SET, PREPARE and DEALLOCATE statements are replicated in
        master/slave mode. (Yoshiyuki Asaba)

===============================================================================

                        1.2 (tomoboshi) 2007/08/01

      * Version 1.2
      * Add new "replicate_select" directive, being the default value
        is false. (Yoshiyuki Asaba)
        - If it is true, SELECT query is replicated. This behavior is
          same as V3.2 or earlier.
      * Improve signal handling. (Yoshiyuki Asaba)
        - Occasionally, zombie processes were remained. Or processes
          were unstable.
      * Fix hang up when SELECT was error inside a transaction
        block. The bug was introduced in V3.3. (Yoshiyuki Asaba)
      * Fix PREPARE/EXECUTE handling in master slave mode. (Yoshiyuki Asaba)
      * Fix "kind mismatch error" when deadlock error
      * Fix hang up and SEGV in extended query protocol when a warning
        SQL like "SELECT '\'';" executed. (Yoshiyuki Asaba)
      * Fix hang up when postmaster did fast or immediate
        shutdown. (Yoshiyuki Asaba)
      * Fix memory leak when connection cache was full. (Yoshiyuki Asaba)
      * Load balancing node is selected when a session
        starts. (Yoshiyuki Asaba)
      * Fix buffer overrun if connection_life_time was
        set. (Yoshiyuki Asaba)


===============================================================================
1.1 Series (2007/5/25 - 2007/6/15)
===============================================================================

                            1.1.1 (amiboshi) 2007/6/15

      * Version 1.1.1
      * Fix "kind mismatch" bug when load_balance_mode is true
        introduced in 1.1 (Yoshiyuki Asaba)
      * Fix deadlock with extended query protocol(Yoshiyuki Asaba)
      * Fix numerous bugs with protocol V2(Yoshiyuki Asaba)

===============================================================================

                            1.1 (amiboshi) 2007/5/25

      * Version 1.1
      * Support HBA authentication(Taiki Yamaguchi)
      * Support log_connections(Taiki Yamaguchi)
      * Support log_hostname(Taiki Yamaguchi)
      * Show pgpool status in ps command(Taiki Yamaguchi)
      * Fix compile error on MacOS X(Yoshiyuki Asaba)
      * Allow load balancing with extended protocol(Yoshiyuki Asaba)
      * Improve replication. SELECT nextval() and SELECT setval() are
        now replicated. (Yoshiyuki Asaba)
      * Change SELECT query is only sent to the master node. (Yoshiyuki Asaba)
        - Use /*REPLICATION*/ comment to replicate a SELECT query.
      * Fix unexpected failover error due to receiving an interrupt
        signal while connecting to the backend. (Yoshiyuki Asaba)
      * Add "pgpool.pam" file, for PAM configuration file, to be
        installed under "$PREFIX/share/pgpool-II/". (Taiki Yamaguchi)
      * Fix core dump when executing large SQL. (Yoshiyuki Asaba)


===============================================================================
1.0 Series (2006/09/08 - 2007/02/12)
===============================================================================

                            1.0.2 (suboshi) 2007/02/12

      * Version 1.0.2
      * Fix bug when executing large SQL to prevent pgpool goes into
        infinite loop(Yoshiyuki Asaba)
      * Fix bug with extended protocol handling(Yoshiyuki Asaba)
      * Enhance log for failover and failback(Tatsuo Ishii)
      * Add backend status info to show pool_status(Tatsuo Ishii)
      * Fix UPDATE/DELETE returns wrong number of rows(Tatsuo Ishii)
      * Fix configure fails to link libpq when used with older
        version of gcc(Yoshiyuki Asaba)
      * Fix DEALLOCATE treatment when used with PHP:PDO DBD-Pg(Yoshiyuki Asaba)
      * Do not load balance SELECT FOR UPDATE, SELECT INTO and SELECT
        with comments. This behavior is compatible with
        pgpool-I(Yoshiyuki Asaba)
      * Obtain path to libpq using pg_config. --with-pgsql will be
        removed in next version(Yoshiyuki Asaba)
      * When reusing connection pool, reconnect to backend if the
        socket is broken(Yoshiyuki Asaba)
      * Fix error with configure when used with PostgreSQL
        7.4(Yoshiyuki Asaba)

===============================================================================

                            1.0.1 (suboshi) 2006/09/22

      * Version 1.0.1
      * This version fixes bugs including master/slave not being
        working, deadlock problem in COPY FROM STDIN. Also documents
        are improved.

===============================================================================

                            1.0 (suboshi) 2006/09/08

      * Initial release

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