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== What is Pgpool-II? ==
 
== What is Pgpool-II? ==
  
pgpool-II is a middleware that works between PostgreSQL servers and a PostgreSQL database client. It is licensed under BSD license. It provides the following features.
+
Pgpool-II is a middleware that works between PostgreSQL servers and a PostgreSQL database client. It is distributed under a license similar to BSD and MIT. It provides the following features.
  
 
* '''Connection Pooling'''
 
* '''Connection Pooling'''
: pgpool-II saves connections to the PostgreSQL servers, and reuse them whenever a new connection with the same properties (i.e. username, database, protocol version) comes in. It reduces connection overhead, and improves system's overall throughput.
+
: Pgpool-II saves connections to the PostgreSQL servers, and reuse them whenever a new connection with the same properties (i.e. username, database, protocol version) comes in. It reduces connection overhead, and improves system's overall throughput.
  
 
* '''Replication'''
 
* '''Replication'''
: pgpool-II can manage multiple PostgreSQL servers. Using the replication function enables creating a realtime backup on 2 or more physical disks, so that the service can continue without stopping servers in case of a disk failure.
+
: Pgpool-II can manage multiple PostgreSQL servers. Using the replication function enables creating a realtime backup on 2 or more physical disks, so that the service can continue without stopping servers in case of a disk failure.
  
 
* '''Load Balancing'''
 
* '''Load Balancing'''
: If a database is replicated, executing a SELECT query on any server will return the same result. pgpool-II takes an advantage of the replication feature to reduce the load on each PostgreSQL server by distributing SELECT queries among multiple servers, improving system's overall throughput. At best, performance improves proportionally to the number of PostgreSQL servers. Load balance works best in a situation where there are a lot of users executing many queries at the same time.
+
: If a database is replicated, executing a SELECT query on any server will return the same result. Pgpool-II takes an advantage of the replication feature to reduce the load on each PostgreSQL server by distributing SELECT queries among multiple servers, improving system's overall throughput. At best, performance improves proportionally to the number of PostgreSQL servers. Load balance works best in a situation where there are a lot of users executing many queries at the same time.
  
 
* '''Limiting Exceeding Connections'''
 
* '''Limiting Exceeding Connections'''
 
: There is a limit on the maximum number of concurrent connections with PostgreSQL, and connections are rejected after this many connections. Setting the maximum number of connections, however, increases resource consumption and affect system performance. pgpool-II also has a limit on the maximum number of connections, but extra connections will be queued instead of returning an error immediately.
 
: There is a limit on the maximum number of concurrent connections with PostgreSQL, and connections are rejected after this many connections. Setting the maximum number of connections, however, increases resource consumption and affect system performance. pgpool-II also has a limit on the maximum number of connections, but extra connections will be queued instead of returning an error immediately.
  
pgpool-II talks PostgreSQL's backend and frontend protocol, and relays a connection between them. Therefore, a database application (frontend) thinks that pgpool-II is the actual PostgreSQL server, and the server (backend) sees pgpool-II as one of its clients. Because pgpool-II is transparent to both the server and the client, an existing database application can be used with pgpool-II almost without a change to its sources.
+
* '''Watchdog'''
 +
: Watchdog can coordinate multiple Pgpool-II, create a robust cluster system and avoid the single point of failure or split brain. Watchdog can perform lifecheck against other pgpool-II nodes, to detect a fault of Pgpoll-II. If active Pgpool-II goes down, standby Pgpool-II can be promoted to active, and take over Virtual IP.
 +
 
 +
* '''In Memory Query Cache'''
 +
: In memory query cache allows to save a pair of SELECT statement and its result. If an identical SELECTs comes in, Pgpool-II returns the value from cache. Since no SQL parsing nor access to PostgreSQL are involved, using in memory cache is extremely fast. On the other hand, it might be slower than the normal path in some cases, because it adds some overhead of storing cache data.
 +
 
 +
Pgpool-II speaks PostgreSQL's backend and frontend protocol, and relays messages between a backend and a frontend. Therefore, a database application (frontend) thinks that Pgpool-II is the actual PostgreSQL server, and the server (backend) sees Pgpool-II as one of its clients. Because Pgpool-II is transparent to both the server and the client, an existing database application can be used with Pgpool-II almost without a
 +
 
 +
Pgpool-II talks PostgreSQL's backend and frontend protocol, and relays a connection between them. Therefore, a database application (frontend) thinks that Pgpool-II is the actual PostgreSQL server, and the server (backend) sees Pgpool-II as one of its clients. Because Pgpool-II is transparent to both the server and the client, an existing database application can be used with Pgpool-II almost without a change to its sources.
  
 
== Pgpool-II License ==
 
== Pgpool-II License ==
  
See [http://pgpool.net/mediawiki/index.php/pgpool-II_License License].
+
See [https://pgpool.net/mediawiki/index.php/pgpool-II_License License].
  
 
== Stable versions ==
 
== Stable versions ==
  
* pgpool-II: 3.6, 3.5, 3.4, 3.3, 3.2, 3.1 '''[Pgpool-II 3.1 will be EOLed in September 2016. Please upgrade.]''' [http://www.pgpool.net/mediawiki/index.php/Source_code_repository#pgpool-II_release_support_policy Support policy]
+
* Pgpool-II: 4.5, 4.4, 4.3, 4.2, 4.1
** 3.0 is obsoleted
 
* pgpoolAdmin: 3.5, 3.4, 3.3
 
* pgpool-HA: 2
 
  
 
== Contacts ==
 
== Contacts ==
  
* If you have technical questions regarding Pgpool-II, please subscribe [http://pgpool.net/mediawiki/index.php/Mailing_lists Pgpool-II mailing lists] and send questions to it (pgpool-general will be a starter). Please '''do not''' send technical questions via private email. We will not respond such that messages.
+
* If you have technical questions regarding Pgpool-II, please subscribe [https://pgpool.net/mediawiki/index.php/Mailing_lists Pgpool-II mailing lists] and send questions to it (pgpool-general will be a starter). Please '''do not''' send technical questions via private email. We will not respond such that messages.
  
 
* If you believe that you found a vulnerability/security issues with Pgpool-II, please send a '''private email''' to ishii at sraoss.co.jp (he is the project leader).
 
* If you believe that you found a vulnerability/security issues with Pgpool-II, please send a '''private email''' to ishii at sraoss.co.jp (he is the project leader).
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== News ==
 
== News ==
  
=== Pgpool-II 3.7 RC1 and pgpoolAdmin 3.7 RC1 released (2017/11/13) ===
+
=== Pgpool-II 4.5.1, 4.4.6, 4.3.9, 4.2.16 and 4.1.19 officially released (2024/02/29) ===
 +
 
 +
Pgpool-II 4.5.1, 4.4.6, 4.3.9, 4.2.16 and 4.1.19 officially released.
  
Pgpool-II 3.7 RC1 is now relased.  
+
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
This is not intended to be used in production but is close to the
 
release version. So users are encouraged to test it out.
 
  
V3.7 has new features:
+
* 4.5.1 :  [https://www.pgpool.net/docs/latest/en/html/release-4-5-1.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-5-1.html Japanese]
* Quorum aware failover feature.
+
* 4.4.6 :  [https://www.pgpool.net/docs/latest/en/html/release-4-4-6.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-4-6.html Japanese]
* Allow specifying the hostnames in pool_hba.
+
* 4.3.9 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-9.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-9.html Japanese]
* Allow to specify per node health check parameters.
+
* 4.2.16 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-16.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-16.html Japanese]
* Support AWS Aurora.
+
* 4.1.19 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-19.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-19.html Japanese]
* Import PostgreSQL 10 SQL parser.
+
 
* Support logical replication.
+
== Events ==
* etc.
+
=== PGConf.ASIA 2019 in Bali ===
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
Bo Peng is going to give a presentation [https://www.sraoss.co.jp/event_seminar/2019/PGConf.ASIA.Bali.2019-PENG.pdf Setup a High-Availability and Load Balancing PostgreSQL Cluster: New Features of Pgpool-II 4.1] at [https://2019.pgconf.asia/ "PGConf.ASIA 2019"] held in Bali from September 8th to 11st.
  
Release notes:
+
=== PGConf.ASIA 2018 in Tokyo ===
[http://www.pgpool.net/docs/pgpool-II-3.7.0/doc/en/html/release-3-7.html English] [http://www.pgpool.net/docs/pgpool-II-3.7.0/doc/ja/html/release-3-7.html Japanese]
 
  
== Events ==
+
Tatsuo Ishii and Bo Peng are going to give a presentation
 +
[https://www.pgpool.net/download.php?f=pgpool-past-now-and-future.pdf Celebrating its 15th Anniversary Pgpool-II Past Present and Future]
 +
[https://www.pgpool.net/download.php?f=pgpool-past-now-and-future-part2.pdf Celebrating its 15th Anniversary Pgpool-II Past Present and Future part2] at [https://www.pgconf.asia/EN/2018/day1/#B4 "PGConf.ASIA 2018"] held in Tokyo from December 10th to 12th.
  
 
=== PGConf.ASIA 2017 in Tokyo ===
 
=== PGConf.ASIA 2017 in Tokyo ===
  
Tatsuo Ishii is going to give a presentation  [http://www.pgconf.asia/EN/2017/day-2/#B5 "More reliability and support for PostgreSQL 10: Introducing Pgpool-II 3.7"] at [http://www.pgconf.asia/EN/2017/ "PGConf.ASIA 2017"], held in Tokyo from December 4th to 6th.
+
Tatsuo Ishii is going to give a presentation  [https://www.pgconf.asia/EN/2017/day-2/#B5 "More reliability and support for PostgreSQL 10: Introducing Pgpool-II 3.7"] at [https://www.pgconf.asia/EN/2017/ "PGConf.ASIA 2017"], held in Tokyo from December 4th to 6th.
  
 
=== PostgreSQL Conference in Russia 2016 ===
 
=== PostgreSQL Conference in Russia 2016 ===
  
 
Tatsuo gave a talk "How to manage a herd of elephants" at [https://pgconf.ru/en "PostgreSQL Conference in Russia 2016"], held in Moscow from February 4th to 5th.
 
Tatsuo gave a talk "How to manage a herd of elephants" at [https://pgconf.ru/en "PostgreSQL Conference in Russia 2016"], held in Moscow from February 4th to 5th.
The slides are available in [http://pgpool.net/mediawiki/index.php/Documentation#Developer.27s_documentation Developer's documentation].
+
The slides are available in [https://pgpool.net/mediawiki/index.php/Documentation#Developer.27s_documentation Developer's documentation].
  
 
=== PostgreSQL Conference in China 2015 ===
 
=== PostgreSQL Conference in China 2015 ===
  
Tatsuo gave a talk "How to manage a herd of elephants" at [http://www.eventdove.com/event/106042 "PostgreSQL Conference in China 2015"], held in Beijing from November 21th to 22th.
+
Tatsuo gave a talk "How to manage a herd of elephants" at [https://www.eventdove.com/event/106042 "PostgreSQL Conference in China 2015"], held in Beijing from November 21th to 22th.
The slides are available in [http://pgpool.net/mediawiki/index.php/Documentation#Developer.27s_documentation Developer's documentation].
+
The slides are available in [https://pgpool.net/mediawiki/index.php/Documentation#Developer.27s_documentation Developer's documentation].
  
 
=== pgCon 2015 Cluster Hacker Summit ===
 
=== pgCon 2015 Cluster Hacker Summit ===
  
We participated "6th Postgres Cluster Hacker Summit" which was held as a part of PgCon 2015 Developer Unconference. We reported about Development Status Updates and pgpool-II 3.5 features. The slides are available in [http://pgpool.net/mediawiki/index.php/Documentation#Developer.27s_documentation Developer's documentation].
+
We participated "6th Postgres Cluster Hacker Summit" which was held as a part of PgCon 2015 Developer Unconference. We reported about Development Status Updates and pgpool-II 3.5 features. The slides are available in [https://pgpool.net/mediawiki/index.php/Documentation#Developer.27s_documentation Developer's documentation].
  
 
=== Pgpool-II Day 2015 in Tokyo ===
 
=== Pgpool-II Day 2015 in Tokyo ===
  
We had the very first time pgpool-II decicated conference. See the [http://pgpool.net/mediawiki/index.php/pgpool-II_Day_2015 event report].
+
We had the very first time pgpool-II decicated conference. See the [https://pgpool.net/mediawiki/index.php/pgpool-II_Day_2015 event report].
 +
 
 +
== Stable ==
 +
 
 +
=== Pgpool-II 4.5.1, 4.4.6, 4.3.9, 4.2.16 and 4.1.19 officially released (2024/02/29) ===
 +
 
 +
Pgpool-II 4.5.1, 4.4.6, 4.3.9, 4.2.16 and 4.1.19 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.5.1 :  [https://www.pgpool.net/docs/latest/en/html/release-4-5-1.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-5-1.html Japanese]
 +
* 4.4.6 :  [https://www.pgpool.net/docs/latest/en/html/release-4-4-6.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-4-6.html Japanese]
 +
* 4.3.9 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-9.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-9.html Japanese]
 +
* 4.2.16 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-16.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-16.html Japanese]
 +
* 4.1.19 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-19.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-19.html Japanese]
 +
 
 +
=== Pgpool-II 4.5.0 released (2023/12/12) ===
 +
 
 +
Pgpool-II 4.5.0 is now released. This is the first stable release of Pgpool-II 4.5.x.
 +
 
 +
V4.5 contains new features and enhancements, including:
 +
 
 +
* Allow to use more kind of multiple statements in a query string.
 +
 
 +
* Allow to load balance PREPARE/EXECUTE/DEALLOCATE.
 +
 
 +
* Allow to set delay_threshold_by_time in milliseconds.
 +
 
 +
* Avoid session disconnection issue in failover/failback/backend error in some cases.
 +
 
 +
* Allow to route queries to a specific backend node for a specific user connection.
 +
 
 +
* Support multiple directories specification for pcp_socket_dir.
 +
 
 +
* Import PostgreSQL 16's SQL parser.
 +
 
 +
You can download it from [https://www.pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
Release notes:
 +
[https://www.pgpool.net/docs/45/en/html/release-4-5-0.html English]
 +
 
 +
=== Pgpool-II 4.4.5, 4.3.8, 4.2.15, 4.1.18 and 4.0.25 officially released (2023/11/30) ===
 +
 
 +
Pgpool-II 4.4.5, 4.3.8, 4.2.15, 4.1.18 and 4.0.25 officially released.
 +
 
 +
Please note that 4.0.25 is the last release of the 4.0.x series.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.4.5 :  [https://www.pgpool.net/docs/latest/en/html/release-4-4-5.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-4-5.html Japanese]
 +
* 4.3.8 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-8.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-8.html Japanese]
 +
* 4.2.15 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-15.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-15.html Japanese]
 +
* 4.1.18 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-18.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-18.html Japanese]
 +
* 4.0.25 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-25.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-25.html Japanese]
 +
 
 +
=== Pgpool-II 4.4.4, 4.3.7, 4.2.14, 4.1.17 and 4.0.24 officially released (2023/08/17) ===
 +
 
 +
Pgpool-II 4.4.4, 4.3.7, 4.2.14, 4.1.17 and 4.0.24 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.4.4 :  [https://www.pgpool.net/docs/latest/en/html/release-4-4-4.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-4-4.html Japanese]
 +
* 4.3.7 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-7.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-7.html Japanese]
 +
* 4.2.14 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-14.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-14.html Japanese]
 +
* 4.1.17 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-17.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-17.html Japanese]
 +
* 4.0.24 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-24.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-24.html Japanese]
  
== New docs ==
+
=== Pgpool-II 4.4.3, 4.3.6, 4.2.13, 4.1.16 and 4.0.23 officially released (2023/05/18) ===
  
=== pgpool-II 3.5 is coming soon! ===
+
Pgpool-II 4.4.3, 4.3.6, 4.2.13, 4.1.16 and 4.0.23 officially released.
  
pgpool-II 3.5 alpha1 has been out. Tatsuo introduces [http://pgpool.net/mediawiki/index.php?title=pgpool-II_3.5_features&redirect=no "new features of pgpool-II 3.5."]
+
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
  
== Stable ==
+
* 4.4.3 :  [https://www.pgpool.net/docs/latest/en/html/release-4-4-3.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-4-3.html Japanese]
 +
* 4.3.6 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-6.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-6.html Japanese]
 +
* 4.2.13 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-13.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-13.html Japanese]
 +
* 4.1.16 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-16.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-16.html Japanese]
 +
* 4.0.23 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-23.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-23.html Japanese]
 +
 
 +
=== End-of-Life (EOL) Announcement for pgpoolAdmin (2023/02/17) ===
 +
 
 +
Pgpool Global Development Group announces end-of-life date for pgpoolAdmin, which is the management tool for Pgpool-II.
 +
 
 +
Pgpool Global Development Group will provide maintenance for pgpoolAdmin 4.0, 4.1 and 4.2 until December 31, 2023.
 +
After this date, bug fixes and security fixes for these versions will no longer be provided.
 +
 
 +
In addition, pgpoolAdmin for Pgpool-II 4.3 or later will not be released.
 +
 
 +
We would like to thank you for using pgpoolAdmin over the years.
 +
 
 +
=== Pgpool-II 4.4.2, 4.3.5, 4.2.12, 4.1.15 and 4.0.22 officially released (2023/01/23) ===
 +
 
 +
Pgpool-II 4.4.2, 4.3.5, 4.2.12, 4.1.15 and 4.0.22 officially released.
 +
 
 +
This release contains a security fix.
 +
 
 +
If following conditions are all met, the password of "wd_lifecheck_user" is exposed by "SHOW POOL STATUS" command.
 +
The command can be executed by any user who can connect to Pgpool-II. (CVE-2023-22332)
 +
* Version 3.3 or later
 +
* use_watchdog = on
 +
* wd_lifecheck_method = 'query'
 +
* A plain text password is set to wd_lifecheck_password
 +
 
 +
In this case it is strongly recommended to upgrade to this version (we do not expose wd_lifecheck_password in show pool_status command any more), or use one of following workarounds.
 +
 
 +
Workarounds for 4.0.x to 4.4.x users:
 +
* Disable watchdog. Set use_watchdog to off.
 +
* Change wd_lifecheck_method to heartbeat.
 +
* Set an empty string to wd_lifecheck_password. This will use password in the pool_passwd file.
 +
* Set an AES encrypted password to wd_lifecheck_password.
 +
 
 +
In any case we recommend to change "wd_lifecheck_password" in PostgreSQL.
 +
 
 +
Workarounds for 3.0.x to 3.7.x users:
 +
* Disable watchdog. Set use_watchdog to off.
 +
* Change wd_lifecheck_method to heartbeat.
 +
 
 +
In any case we recommend to change "wd_lifecheck_password" in PostgreSQL.
 +
 
 +
Please note that Pgpool-II 3.7.x or before are end of life and no minor updates are provided for those versions.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.4.2 :  [https://www.pgpool.net/docs/latest/en/html/release-4-4-1.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-4-2.html Japanese]
 +
* 4.3.5 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-4.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-5.html Japanese]
 +
* 4.2.12 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-11.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-12.html Japanese]
 +
* 4.1.15 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-14.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-15.html Japanese]
 +
* 4.0.22 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-21.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-22.html Japanese]
 +
 
 +
=== Pgpool-II 4.4.1, 4.3.4, 4.2.11, 4.1.14, 4.0.21 and 3.7.26 officially released (2022/12/22) ===
 +
 
 +
Pgpool-II 4.4.1, 4.3.4, 4.2.11, 4.1.14, 4.0.21 and 3.7.26 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.4.1 :  [https://www.pgpool.net/docs/latest/en/html/release-4-4-1.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-4-1.html Japanese]
 +
* 4.3.4 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-4.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-4.html Japanese]
 +
* 4.2.11 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-11.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-11.html Japanese]
 +
* 4.1.14 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-14.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-14.html Japanese]
 +
* 4.0.21 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-21.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-21.html Japanese]
 +
* 3.7.26 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-26.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-26.html Japanese]
 +
 
 +
=== Pgpool-II 4.4.0 released (2022/12/06) ===
 +
 
 +
Pgpool-II 4.4.0 is now released. This is the first stable release of Pgpool-II 4.4.x.
 +
 
 +
V4.4 contains new features and enhancements, including:
 +
 
 +
* Add new dynamic spare process management feature. This feature allows selecting between static and dynamic process management modes.
 +
 
 +
* Allow to specify replication delay by time in streaming replication mode. For this purpose new parameter delay_threshold_by_time is introduced.
 +
 
 +
* As PostgreSQL already does, Pgpool-II now supports unix_socket_directories, unix_socket_group and unix_socket_permissions for more flexible and precise control of UNIX domain sockets.
 +
 
 +
* Allow to use comma separated multiple listen addresses in listen_addresses and pcp_listen_addresses. They control which interfaces accept connection attempts, which can help prevent repeated malicious connection requests on insecure network interfaces.
 +
 
 +
* Allow to customize the command used by trusted_servers for checking upstream connection. For this purpose new parameter trusted_server_command is introduced.
 +
 
 +
* Import PostgreSQL 15's SQL parser.
 +
 
 +
* Speed up query cache by reducing lock contention. This allows concurrent running clients to fetch cache contents much more quicker.
 +
 
 +
You can download it from [https://www.pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
Release notes:
 +
[https://www.pgpool.net/docs/44/en/html/release-4-4-0.html English] [https://www.pgpool.net/docs/44/ja/html/release-4-4-0.html Japanese]
 +
 
 +
=== Pgpool-II 4.3.3, 4.2.10, 4.1.13, 4.0.20 and 3.7.25 officially released (2022/08/18) ===
 +
 
 +
Pgpool-II 4.3.3, 4.2.10, 4.1.13, 4.0.20 and 3.7.25 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.3.3 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-3.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-3.html Japanese]
 +
* 4.2.10 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-10.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-10.html Japanese]
 +
* 4.1.13 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-13.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-13.html Japanese]
 +
* 4.0.20 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-20.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-20.html Japanese]
 +
* 3.7.25 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-25.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-25.html Japanese]
 +
 
 +
=== Pgpool-II 4.3.2, 4.2.9, 4.1.12, 4.0.19 and 3.7.24 officially released (2022/05/19) ===
 +
 
 +
Pgpool-II 4.3.2, 4.2.9, 4.1.12, 4.0.19 and 3.7.24 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.3.2 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-2.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-2.html Japanese]
 +
* 4.2.9 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-9.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-9.html Japanese]
 +
* 4.1.12 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-12.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-12.html Japanese]
 +
* 4.0.19 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-19.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-19.html Japanese]
 +
* 3.7.24 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-24.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-24.html Japanese]
 +
 
 +
=== Pgpool-II 4.3.1, 4.2.8, 4.1.11, 4.0.18 and 3.7.23 officially released (2022/02/17) ===
 +
 
 +
Pgpool-II 4.3.1, 4.2.8, 4.1.11, 4.0.18 and 3.7.23 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.3.1 :  [https://www.pgpool.net/docs/latest/en/html/release-4-3-1.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-3-1.html Japanese]
 +
* 4.2.8 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-8.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-8.html Japanese]
 +
* 4.1.11 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-11.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-11.html Japanese]
 +
* 4.0.18 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-18.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-18.html Japanese]
 +
* 3.7.23 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-23.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-23.html Japanese]
 +
 
 +
=== Pgpool-II 4.2.7, 4.1.10, 4.0.17 and 3.7.22 officially released (2021/12/23) ===
 +
 
 +
Pgpool-II 4.2.7, 4.1.10, 4.0.17 and 3.7.22 officially released.
 +
 
 +
The purpose of this release is to provide packages for PostgreSQL 14.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.2.7 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-7.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-7.html Japanese]
 +
* 4.1.10 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-10.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-10.html Japanese]
 +
* 4.0.17 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-17.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-17.html Japanese]
 +
* 3.7.22 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-22.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-22.html Japanese]
 +
 
 +
=== Pgpool-II 4.3.0 released (2021/12/07) ===
 +
 
 +
Pgpool-II 4.3.0 is now released. Please take a look at [https://www.pgpool.net/docs/43/en/html/release-4-3-0.html 4.3.0]
 +
 
 +
V4.3.0 contains new features and enhancements, including:
 +
* A new membership mechanism is introduced to Watchdog to allow to keep quorum/VIP when some of watchdog nodes are removed.
 +
 
 +
* Allow to choose the least replication delay standby node when selecting the load balance node.
 +
 
 +
* Allow to specify the node id to be promoted in pcp_promote_node.
 +
 
 +
* Allow to configure to not trigger failover when PostgreSQL is shutdown by admin or killed by pg_terminate_backend.
 +
 
 +
* Add new fields to pcp_proc_info, SHOW POOL_PROCESSES and SHOW POOL_POOLS command to display more useful information to admin.
 +
 
 +
* Allow pcp_node_info to list all backend nodes information.
 +
 
 +
* Add new fields showing actual PostgreSQL status to SHOW POOL NODES command and friends.
 +
 
 +
* Add a new parameter which represents the recovery source hostname to recovery_1st_stage_command and recovery_2nd_stage_command.
 +
 
 +
* Add support for log time stamp with milliseconds.
 +
 
 +
* Import PostgreSQL 14's SQL parser.
 +
 
 +
* Support include directive in pgppol.conf file. You can have separate sub-config file to be included in pgpool.conf.
 +
 
 +
* pgpool.conf sample files are unified into single sample file for easier configuration.
 +
 
 +
* All configuration parameters in pgpool.conf sample file are commented out to clarify which parameter is needed to be changed.
 +
 
 +
You can download it from [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
Release notes:
 +
[https://www.pgpool.net/docs/43/en/html/release-4-3-0.html English]
 +
 
 +
=== Pgpool-II 4.2.6, 4.1.9, 4.0.16, 3.7.21 and 3.6.28 officially released (2021/11/18) ===
 +
 
 +
Pgpool-II 4.2.6, 4.1.9, 4.0.16, 3.7.21 and 3.6.28 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.2.6 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-6.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-6.html Japanese]
 +
* 4.1.9 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-9.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-9.html Japanese]
 +
* 4.0.16 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-16.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-16.html Japanese]
 +
* 3.7.21 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-21.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-21.html Japanese]
 +
* 3.6.28 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-28.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-28.html Japanese]
 +
 
 +
=== Pgpool-II 4.2.5 released (2021/09/14) ===
 +
 
 +
Pgpool Global Development Group is pleased to announce the availability of Pgpool-II 4.2.5.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.2.5 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-5.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-5.html Japanese]
 +
 
 +
=== Pgpool-II 4.2.4, 4.1.8, 4.0.15, 3.7.20 and 3.6.27 officially released (2021/08/05) ===
 +
 
 +
Pgpool-II 4.2.4, 4.1.8, 4.0.15, 3.7.20 and 3.6.27 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.2.4 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-4.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-4.html Japanese]
 +
* 4.1.8 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-8.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-8.html Japanese]
 +
* 4.0.15 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-15.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-15.html Japanese]
 +
* 3.7.20 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-20.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-20.html Japanese]
 +
* 3.6.27 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-27.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-27.html Japanese]
 +
 
 +
=== pgpoolAdmin 4.2.0 officially released (2021/06/17) ===
 +
 
 +
pgpoolAdmin 4.2.0 officially released.
 +
 
 +
pgpoolAdmin 4.2.0 adds support for Pgpool-II 4.2.
 +
Please take a look at [https://www.pgpool.net/docs/pgpoolAdmin/NEWS release notes].
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
=== Pgpool-II 4.2.3, 4.1.7, 4.0.14, 3.7.19 and 3.6.26 officially released (2021/05/20) ===
 +
 
 +
Pgpool-II 4.2.3, 4.1.7, 4.0.14, 3.7.19 and 3.6.26 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.2.3 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-3.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-3.html Japanese]
 +
* 4.1.7 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-7.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-7.html Japanese]
 +
* 4.0.14 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-14.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-14.html Japanese]
 +
* 3.7.19 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-19.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-19.html Japanese]
 +
* 3.6.26 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-26.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-26.html Japanese]
 +
 
 +
=== Pgpool-II 4.2.2, 4.1.6, 4.0.13, 3.7.18 and 3.6.25 officially released (2021/02/18) ===
 +
 
 +
Pgpool-II 4.2.2, 4.1.6, 4.0.13, 3.7.18 and 3.6.25 officially released.
 +
 
 +
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.2.2 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-2.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-2.html Japanese]
 +
* 4.1.6 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-6.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-6.html Japanese]
 +
* 4.0.13 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-13.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-13.html Japanese]
 +
* 3.7.18 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-18.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-18.html Japanese]
 +
* 3.6.25 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-25.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-25.html Japanese]
 +
 
 +
=== Pgpool-II 4.2.1 released (2020/12/23) ===
 +
 
 +
Pgpool-II 4.2.1 is now released.
 +
 
 +
You can download them from [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
* 4.2.1 :  [https://www.pgpool.net/docs/latest/en/html/release-4-2-1.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-2-1.html Japanese]
 +
 
 +
=== Pgpool-II 4.2.0 released (2020/11/26) ===
 +
 
 +
Pgpool-II 4.2.0 is now released.
 +
 
 +
V4.2 contains new features and enhancements, including:
 +
 
 +
* Some items in the configuration file pgpool.conf are vastly enhanced for easier configuration and administration.
 +
 
 +
* Implement logging_collector for easier log management.
 +
 
 +
* Implement log_disconnections to collect disconnection logs.
  
=== Pgpool-II 3.6.7, 3.5.11, 3.4.14 and 3.3.18 officially released (2017/11/01) ===
+
* Implement pg_enc and pg_md5 to allow to register multiple passwords at once.
  
Pgpool-II 3.6.7, 3.5.11, 3.4.14 and 3.3.18 officially released
+
* Allow to show statistics of health check by using SHOW POOL_HEALTH_CHECK_STATS command, and also allow to show statistics of issued SQL by using SHOW POOL_BACKEND_STATS command.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* New PCP command pcp_reload_config is added.
  
* 3.6.7 :  [http://www.pgpool.net/docs/latest/en/html/release-3-6-7.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-6-7.html Japanese]
+
* Now it is possible to omit write_function_list and read_only_function_list by looking at system catalog information.
* 3.5.11 :  [http://www.pgpool.net/docs/latest/en/html/release-3-5-11.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-5-11.html Japanese]
 
* 3.4.14:  [http://www.pgpool.net/docs/latest/en/html/release-3-4-14.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-4-14.html Japanese]
 
* 3.3.18:  [http://www.pgpool.net/docs/latest/en/html/release-3-3-18.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-3-18.html Japanese]
 
  
=== Pgpool-II 3.6.6, 3.5.10, 3.4.13, 3.3.17 and 3.2.22 officially released (2017/09/05) ===
+
* Add new clustering mode snapshot_isolation_mode which guarantees not only data modifications to multiple PostgreSQL but read consistency.
  
Pgpool-II 3.6.6, 3.5.10, 3.4.13, 3.3.17, 3.2.22 and pgpoolAdmin 3.6.2 officially released
+
* Support LDAP authentication between clients and Pgpool-II.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Add ssl_crl_file and ssl_passphrase_command to SSL configuration.
  
* 3.6.6 :  [http://www.pgpool.net/docs/latest/en/html/release-3-6-6.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-6-6.html Japanese]
+
* Import PostgreSQL 13's SQL parser.  
* 3.5.10 :  [http://www.pgpool.net/docs/latest/en/html/release-3-5-10.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-5-10.html Japanese]
 
* 3.4.13:  [http://www.pgpool.net/docs/latest/en/html/release-3-4-13.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-4-13.html Japanese]
 
* 3.3.17:  [http://www.pgpool.net/docs/latest/en/html/release-3-3-17.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-3-17.html Japanese]
 
* 3.2.22:  [http://www.pgpool.net/docs/latest/en/html/release-3-2-22.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-2-22.html Japanese]
 
  
=== Pgpool-II 3.6.5, 3.5.9, 3.4.12, 3.3.16 and 3.2.21 officially released (2017/07/11) ===
+
You can download it from [https://pgpool.net/mediawiki/index.php/Downloads here].
  
Pgpool-II 3.6.5, 3.5.9, 3.4.12, 3.3.16 and 3.2.21 officially released
+
Release notes:
 +
[https://www.pgpool.net/docs/42/en/html/release-4-2-0.html English]
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
=== Pgpool-II 4.1.5, 4.0.12, 3.7.17, 3.6.24 and 3.5.28 officially released (2020/11/19) ===
  
* 3.6.5 :  [http://www.pgpool.net/docs/latest/en/html/release-3-6-5.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-6-5.html Japanese]
+
Pgpool-II 4.1.5, 4.0.12, 3.7.17, 3.6.24 and 3.5.28 officially released
* 3.5.9 :  [http://www.pgpool.net/docs/latest/en/html/release-3-5-9.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-5-9.html Japanese]
 
* 3.4.12:  [http://www.pgpool.net/docs/latest/en/html/release-3-4-12.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-4-12.html Japanese]
 
* 3.3.16:  [http://www.pgpool.net/docs/latest/en/html/release-3-3-16.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-3-16.html Japanese]
 
* 3.2.21:  [http://www.pgpool.net/docs/latest/en/html/release-3-2-21.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-2-21.html Japanese]
 
  
=== Pgpool-II 3.6.4, 3.5.8 officially released (2017/05/11) ===
+
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
  
Pgpool-II 3.6.4, 3.5.8 officially released
+
* 4.1.5 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-5.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-5.html Japanese]
 +
* 4.0.12 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-12.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-12.html Japanese]
 +
* 3.7.17 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-17.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-17.html Japanese]
 +
* 3.6.24 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-24.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-24.html Japanese]
 +
* 3.5.28 :  [https://www.pgpool.net/docs/latest/en/html/release-3-5-28.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-5-28.html Japanese]
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
=== Pgpool-II 4.1.4, 4.0.11, 3.7.16, 3.6.23 and 3.5.27 officially released (2020/09/17) ===
  
* 3.6.4:  [http://www.pgpool.net/docs/latest/en/html/release-3-6-4.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-6-4.html Japanese]
+
Pgpool-II 4.1.4, 4.0.11, 3.7.16, 3.6.23 and 3.5.27 officially released
* 3.5.8:  [http://www.pgpool.net/docs/latest/en/html/release-3-5-8.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-5-8.html Japanese]
 
  
=== Pgpool-II 3.6.3, 3.5.7, 3.4.11, 3.3.15, 3.2.20 and pgpoolAdmin 3.6.1 officially released (2017/04/28) ===
+
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
  
Pgpool-II 3.6.3, 3.5.7, 3.4.11, 3.3.15, 3.2.20 and pgpoolAdmin 3.6.1 officially released
+
* 4.1.4 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-4.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-4.html Japanese]
 +
* 4.0.11 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-11.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-11.html Japanese]
 +
* 3.7.16 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-16.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-16.html Japanese]
 +
* 3.6.23 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-23.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-23.html Japanese]
 +
* 3.5.27 :  [https://www.pgpool.net/docs/latest/en/html/release-3-5-27.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-5-27.html Japanese]
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
=== Pgpool-II 4.1.3, 4.0.10, 3.7.15, 3.6.22 and 3.5.26 officially released (2020/08/20) ===
  
* 3.6.3:  [http://www.pgpool.net/docs/latest/en/html/release-3-6-3.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-6-3.html Japanese]
+
Pgpool-II 4.1.3, 4.0.10, 3.7.15, 3.6.22 and 3.5.26 officially released
* 3.5.7:  [http://www.pgpool.net/docs/latest/en/html/release-3-5-7.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-5-7.html Japanese]
 
* 3.4.11:  [http://www.pgpool.net/docs/latest/en/html/release-3-4-11.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-4-11.html Japanese]
 
* 3.3.15:  [http://www.pgpool.net/docs/latest/ja/html/release-3-3-15.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-3-15.html Japanese]
 
* 3.2.20:  [http://www.pgpool.net/docs/latest/ja/html/release-3-2-20.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-2-20.html Japanese]
 
  
=== Pgpool-II 3.6.2, 3.5.6, 3.4.10, 3.3.14 and 3.2.19 officially released (2017/03/17) ===
+
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
  
Pgpool-II 3.6.2, 3.5.6, 3.4.10, 3.3.14 and 3.2.19 officially released
+
* 4.1.3 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-3.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-3.html Japanese]
 +
* 4.0.10 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-10.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-10.html Japanese]
 +
* 3.7.15 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-15.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-15.html Japanese]
 +
* 3.6.22 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-22.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-22.html Japanese]
 +
* 3.5.26 :  [https://www.pgpool.net/docs/latest/en/html/release-3-5-26.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-5-26.html Japanese]
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
=== Pgpool-II 4.1.2, 4.0.9, 3.7.14, 3.6.21 and 3.5.25 officially released (2020/05/21) ===
  
* 3.6.2:  [http://www.pgpool.net/docs/latest/en/html/release-3-6-2.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-6-2.html Japanese]
+
Pgpool-II 4.1.2, 4.0.9, 3.7.14, 3.6.21 and 3.5.25 officially released
* 3.5.6:  [http://www.pgpool.net/docs/latest/en/html/release-3-5-6.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-5-6.html Japanese]
 
* 3.4.10:  [http://www.pgpool.net/docs/latest/en/html/release-3-4-10.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-4-10.html Japanese]
 
* 3.3.14:  [http://www.pgpool.net/docs/latest/ja/html/release-3-3-14.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-3-14.html Japanese]
 
* 3.2.19:  [http://www.pgpool.net/docs/latest/ja/html/release-3-2-19.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-2-19.html Japanese]
 
  
=== pgpoolAdmin 3.6.0 officially released (2017/02/28) ===
+
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
  
pgpoolAdmin 3.6.0 is officially released.
+
* 4.1.2 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-2.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-2.html Japanese]
 +
* 4.0.9 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-9.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-9.html Japanese]
 +
* 3.7.14 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-14.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-14.html Japanese]
 +
* 3.6.21 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-21.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-21.html Japanese]
 +
* 3.5.25 :  [https://www.pgpool.net/docs/latest/en/html/release-3-5-25.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-5-25.html Japanese]
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
=== Pgpool-II 4.1.1, 4.0.8, 3.7.13, 3.6.20, 3.5.24 and pgpoolAdmin 4.1.0 officially released (2020/02/20) ===
  
=== pgpool-II 3.6.1, 3.5.5, 3.4.9, 3.3.13, 3.2.18 and 3.1.21 officially released (2016/12/26) ===
+
Pgpool-II 4.1.1, 4.0.8, 3.7.13, 3.6.20, 3.5.24 and pgpoolAdmin 4.1.0 officially released
  
These are the latest stable versions of each major branches.  
+
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* 4.1.1 :  [https://www.pgpool.net/docs/latest/en/html/release-4-1-1.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-1-1.html Japanese]
 +
* 4.0.8 :  [https://www.pgpool.net/docs/latest/en/html/release-4-0-8.html English] [https://www.pgpool.net/docs/latest/ja/html/release-4-0-8.html Japanese]
 +
* 3.7.13 :  [https://www.pgpool.net/docs/latest/en/html/release-3-7-13.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-7-13.html Japanese]
 +
* 3.6.20 :  [https://www.pgpool.net/docs/latest/en/html/release-3-6-20.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-6-20.html Japanese]
 +
* 3.5.24 :  [https://www.pgpool.net/docs/latest/en/html/release-3-5-24.html English] [https://www.pgpool.net/docs/latest/ja/html/release-3-5-24.html Japanese]
  
* 3.6.1:  [http://www.pgpool.net/docs/latest/en/html/release-3-6-1.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-6-1.html Japanese]
+
=== Pgpool-II 4.1.0, 4.0.7, 3.7.12, 3.6.19, 3.5.23 and 3.4.26 RPMs Update 2 officially released (2019/11/19) ===
* 3.5.5:  [http://www.pgpool.net/docs/latest/en/html/release-3-5-5.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-5-5.html Japanese]
 
* 3.4.9:  [http://www.pgpool.net/docs/latest/en/html/release-3-4-9.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-4-9.html Japanese]
 
* 3.3.13:  [http://www.pgpool.net/docs/latest/en/html/release-3-3-13.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-3-13.html Japanese]
 
* 3.2.18:  [http://www.pgpool.net/docs/latest/en/html/release-3-2-18.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-2-18.html Japanese]
 
* 3.1.21:  [http://www.pgpool.net/docs/latest/en/html/release-3-1-21.html English] [http://www.pgpool.net/docs/latest/ja/html/release-3-1-21.html Japanese]
 
  
pgpool-II 3.1.21 is the final release of the 3.1.x. This series has reached "End of Life", and is no longer maintained and does not receive any updates.  
+
Pgpool-II 4.1.0, 4.0.7, 3.7.12, 3.6.19, 3.5.23 and 3.4.26 RPMs Update 2 are officially released.
 +
The updated RPM packages fixed the bug which logs are not output, when log_destination = 'syslog' is configured.
  
=== pgpool-II 3.6.0 officially released (2016/11/21) ===
+
You can download them [https://pgpool.net/mediawiki/index.php/Downloads here].
  
Pgpool-II 3.6.0 is now officially released.
+
=== Pgpool-II 4.1.0 released (2019/10/31) ===
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
Pgpool-II 4.1.0 is now relased.  
  
V3.6's new features are:
+
Major enhancements in Pgpool-II 4.1 include:
  
* Improve the behavior of fail-over.
+
* Statement level load balancing.
* New PGPOOL SET command has been introduced.
+
* Auto failback.
* Watchdog is significantly enhanced.
+
* Enhance performance in number of areas.
* 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.
+
** Shared relation cache allows to reuse relation cache among sessions to reduce internal queries against PostgreSQL system catalogs.
* Import parser of PostgreSQL 9.6.
+
** Have separate SQL parser for DML statements to eliminate unnecessary parsing effort.
* In some cases pg_terminate_backend() now does not trigger a fail-over.
+
** Load balancing control for specific queries.  
* Change documentation format from raw HTML to SGML.
+
* Reduce Internal Queries against System Catalogs.
 +
* Import PostgreSQL 12 SQL parser.  
 
* etc.
 
* etc.
  
=== pgpool-II 3.5.4, 3.4.8, 3.3.12, 3.2.17 and 3.1.20 officially released (2016/08/31) ===
+
You can download it from [https://pgpool.net/mediawiki/index.php/Downloads here].
 +
 
 +
Release notes:
 +
[https://www.pgpool.net/docs/latest/en/html/ English]
 +
[https://www.pgpool.net/docs/latest/ja/html/ Japanese]
 +
 
 +
== Development ==
 +
 
 +
=== Pgpool-II 4.5 RC1 released (2023/11/28) ===
 +
 
 +
Pgpool-II 4.5 RC1 is now released.
 +
 
 +
Note that this is not a stable version but just for developers.
  
These are the latest stable versions of each major branches.  
+
V4.5 contains new features and enhancements, including:
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Allow to use multiple statements in a query string.
  
* 3.5.4:  [http://www.pgpool.net/docs/pgpool-II-3.5.4/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.5.4/doc/pgpool-ja.html#release3.5.4 Japanese]
+
* Allow to set delay_threshold_by_time in milliseconds.
* 3.4.8:  [http://www.pgpool.net/docs/pgpool-II-3.4.8/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.8/doc/pgpool-ja.html#release3.4.8 Japanese]
 
* 3.3.12:  [http://www.pgpool.net/docs/pgpool-II-3.3.12/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.12/doc/pgpool-ja.html#release3.3.12 Japanese]
 
* 3.2.17:  [http://www.pgpool.net/docs/pgpool-II-3.2.17/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.17/doc/pgpool-ja.html#release3.2.17 Japanese]
 
* 3.1.20: [http://www.pgpool.net/docs/pgpool-II-3.1.20/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.20/doc/pgpool-ja.html#release3.1.20 Japanese]
 
  
=== pgpool-II 3.5.3, 3.4.7, 3.3.11, 3.2.16, 3.1.19, and pgpoolAdmin 3.5.3 officially released (2016/06/17) ===
+
* Avoid session disconnection issue in failover/failback/backend error in some cases.
  
These are the latest stable versions of each major branches.  
+
* Allow to route queries to a specific backend node for a specific user connection.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Support multiple directories specification for pcp_socket_dir.
  
* 3.5.3:  [http://www.pgpool.net/docs/pgpool-II-3.5.3/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.5.3/doc/pgpool-ja.html#release3.5.3 Japanese]
+
* Import PostgreSQL 16's SQL parser.  
* 3.4.7:  [http://www.pgpool.net/docs/pgpool-II-3.4.7/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.7/doc/pgpool-ja.html#release3.4.7 Japanese]
 
* 3.3.11:  [http://www.pgpool.net/docs/pgpool-II-3.3.11/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.11/doc/pgpool-ja.html#release3.3.11 Japanese]
 
* 3.2.16:  [http://www.pgpool.net/docs/pgpool-II-3.2.16/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.16/doc/pgpool-ja.html#release3.2.16 Japanese]
 
* 3.1.19: [http://www.pgpool.net/docs/pgpool-II-3.1.19/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.19/doc/pgpool-ja.html#release3.1.19 Japanese]
 
  
=== pgpool-II 3.5.2, 3.4.6, 3.3.10, 3.2.15, 3.1.18, and pgpoolAdmin 3.5.2 officially released (2016/04/26) ===
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
 +
 
 +
Release notes:
 +
[https://www.pgpool.net/docs/45/en/html/release-4-5-0.html English]
  
These are the latest stable versions of each major branches.  
+
=== Pgpool-II 4.5 beta1 released (2023/11/14) ===
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
Pgpool-II 4.5 beta1 is now released.  
  
* 3.5.2:  [http://www.pgpool.net/docs/pgpool-II-3.5.2/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.5.2/doc/pgpool-ja.html#release3.5.2 Japanese]
+
Note that this is not a stable version but just for developers.
* 3.4.6:  [http://www.pgpool.net/docs/pgpool-II-3.4.6/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.6/doc/pgpool-ja.html#release3.4.6 Japanese]
 
* 3.3.10:  [http://www.pgpool.net/docs/pgpool-II-3.3.10/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.10/doc/pgpool-ja.html#release3.3.10 Japanese]
 
* 3.2.15:  [http://www.pgpool.net/docs/pgpool-II-3.2.15/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.15/doc/pgpool-ja.html#release3.2.15 Japanese]
 
* 3.1.18: [http://www.pgpool.net/docs/pgpool-II-3.1.18/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.18/doc/pgpool-ja.html#release3.1.18 Japanese]
 
  
=== pgpool-II 3.5.1, 3.4.5, 3.3.9, 3.2.14, 3.1.17, and pgpoolAdmin 3.5.1 officially released (2016/04/04) ===
+
V4.5 contains new features and enhancements, including:
  
These are the latest stable versions of each major branches.  
+
* Allow to use multiple statements in a query string.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Allow to set delay_threshold_by_time in milliseconds.
  
* 3.5.1:  [http://www.pgpool.net/docs/pgpool-II-3.5.1/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.5.1/doc/pgpool-ja.html#release3.5.1 Japanese]
+
* Avoid session disconnection issue in failover/failback/backend error in some cases.
* 3.4.5:  [http://www.pgpool.net/docs/pgpool-II-3.4.5/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.5/doc/pgpool-ja.html#release3.4.5 Japanese]
 
* 3.3.9:  [http://www.pgpool.net/docs/pgpool-II-3.3.9/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.9/doc/pgpool-ja.html#release3.3.9 Japanese]
 
* 3.2.14:  [http://www.pgpool.net/docs/pgpool-II-3.2.14/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.14/doc/pgpool-ja.html#release3.2.14 Japanese]
 
* 3.1.17: [http://www.pgpool.net/docs/pgpool-II-3.1.17/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.17/doc/pgpool-ja.html#release3.1.17 Japanese]
 
  
=== pgpool-II 3.4.4, 3.3.8, 3.2.13, 3.1.16, and 3.0.20 officially released (2016/02/05) ===
+
* Allow to route queries to a specific backend node for a specific user connection.
  
These are the latest stable versions of each major branches.  
+
* Support multiple directories specification for pcp_socket_dir.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Import PostgreSQL 16's SQL parser.  
  
* 3.4.4:  [http://www.pgpool.net/docs/pgpool-II-3.4.4/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.4/doc/pgpool-ja.html#release3.4.4 Japanese]
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
* 3.3.8:  [http://www.pgpool.net/docs/pgpool-II-3.3.8/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.8/doc/pgpool-ja.html#release3.3.8 Japanese]
 
* 3.2.13:  [http://www.pgpool.net/docs/pgpool-II-3.2.13/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.13/doc/pgpool-ja.html#release3.2.13 Japanese]
 
* 3.1.16: [http://www.pgpool.net/docs/pgpool-II-3.1.16/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.16/doc/pgpool-ja.html#release3.1.16 Japanese]
 
* 3.0.20: [http://www.pgpool.net/docs/pgpool-II-3.0.20/doc/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.0.20/doc/pgpool-ja.html#release3.0.20 Japanese]
 
  
pgpool-II 3.0.20 is the final release of the 3.0.x. This series has reached "End of Life", and is no longer maintained and does not receive any updates.
+
Release notes:
 +
[https://www.pgpool.net/docs/45/en/html/release-4-5-0.html English]
  
=== pgpool-II 3.5.0 and pgpoolAdmin 3.5.0 officially released (2016/01/29) ===
+
=== Pgpool-II 4.4 RC1 released (2022/11/22) ===
  
Pgpool-II 3.5.0 and pgpoolAdmin 3.5.0 are now officially released.
+
Pgpool-II 4.4 RC1 is now released.  
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
Note that this is not a stable version but just for developers.
  
 +
V4.4 contains new features and enhancements, including:
  
V3.5's new features are:
+
* Add new dynamic spare process management feature. This feature allows selecting between static and dynamic process management modes.
  
* Improved performance in extended query protocol
+
* Allow to specify replication delay by time in streaming replication mode. For this purpose new parameter delay_threshold_by_time is introduced.
* Overcoming the thundering herd problem
 
* watchdog feature enhancements to be more robust and adaptable
 
* PCP command enhancements
 
* Import PostgreSQL 9.5 parser
 
* etc.
 
  
Please see [http://pgpool.net/mediawiki/index.php?title=pgpool-II_3.5_features&redirect=no this] for details.
+
* As PostgreSQL already does, Pgpool-II now supports unix_socket_directories, unix_socket_group and unix_socket_permissions for more flexible and precise control of UNIX domain sockets.
  
 +
* Allow to use comma separated multiple listen addresses in listen_addresses and pcp_listen_addresses. They control which interfaces accept connection attempts, which can help prevent repeated malicious connection requests on insecure network interfaces.
  
3.5.0 release note:  [http://www.pgpool.net/docs/pgpool-II-3.5.0/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.5.0/doc/pgpool-ja.html#release3.5.0 Japanese]
+
* Allow to customize the command used by trusted_servers for checking upstream connection. For this purpose new parameter trusted_server_command is introduced.
  
=== pgpool-II 3.4.3, 3.3.7, 3.2.12, 3.1.15, and 3.0.19 officially released (2015/07/24) ===
+
* Import PostgreSQL 15's SQL parser.
  
These are the latest stable versions of each major branches.  
+
* Speed up query cache by reducing lock contention. This allows concurrent running clients to fetch cache contents much more quicker.  
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
  
* 3.4.3: [http://www.pgpool.net/docs/pgpool-II-3.4.3/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.3/doc/pgpool-ja.html#release3.4.3 Japanese]
+
Release notes:
* 3.3.7:  [http://www.pgpool.net/docs/pgpool-II-3.3.7/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.7/doc/pgpool-ja.html#release3.3.7 Japanese]
+
[https://www.pgpool.net/docs/44/en/html/release-4-4-0.html English]
* 3.2.12:  [http://www.pgpool.net/docs/pgpool-II-3.2.12/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.12/doc/pgpool-ja.html#release3.2.12 Japanese]
 
* 3.1.15: [http://www.pgpool.net/docs/pgpool-II-3.1.15/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.15/doc/pgpool-ja.html#release3.1.15 Japanese]
 
* 3.0.19: [http://www.pgpool.net/docs/pgpool-II-3.0.19/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.0.19/doc/pgpool-ja.html#release3.0.19 Japanese]
 
  
 +
=== Pgpool-II 4.4 beta1 released (2022/11/14) ===
  
=== pgpool-II 3.4.2, 3.3.6, 3.2.11, 3.1.14, and 3.0.18 officially released (2015/04/08) ===
+
Pgpool-II 4.4 beta1 is now released.  
  
These are the latest stable versions of each major branches.  
+
Note that this is not a stable version but just for developers.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
V4.4 contains new features and enhancements, including:
  
* 3.4.2:  [http://www.pgpool.net/docs/pgpool-II-3.4.2/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.2/doc/pgpool-ja.html#release3.4.2 Japanese]
+
* Add new dynamic spare process management feature. This feature allows selecting between static and dynamic process management modes.
* 3.3.6:  [http://www.pgpool.net/docs/pgpool-II-3.3.6/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.6/doc/pgpool-ja.html#release3.3.6 Japanese]
 
* 3.2.11:  [http://www.pgpool.net/docs/pgpool-II-3.2.11/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.11/doc/pgpool-ja.html#release3.2.11 Japanese]
 
* 3.1.14: [http://www.pgpool.net/docs/pgpool-II-3.1.14/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.14/doc/pgpool-ja.html#release3.1.14 Japanese]
 
* 3.0.18: [http://www.pgpool.net/docs/pgpool-II-3.0.18/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.0.18/doc/pgpool-ja.html#release3.0.18 Japanese]
 
  
=== pgpool-II 3.4.1, 3.3.5, 3.2.10, 3.1.13, 3.0.17  and pgpoolAdmin 3.4.1 officially released (2015/02/05) ===
+
* Allow to specify replication delay by time in streaming replication mode. For this purpose new parameter delay_threshold_by_time is introduced.
  
These are the latest stable versions of each major branches.  
+
* As PostgreSQL already does, Pgpool-II now supports unix_socket_directories, unix_socket_group and unix_socket_permissions for more flexible and precise control of UNIX domain sockets.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Allow to use comma separated multiple listen addresses in listen_addresses and pcp_listen_addresses. They control which interfaces accept connection attempts, which can help prevent repeated malicious connection requests on insecure network interfaces.
  
* 3.4.1:  [http://www.pgpool.net/docs/pgpool-II-3.4.1/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.1/doc/pgpool-ja.html#release3.4.1 Japanese]
+
* Allow to customize the command used by trusted_servers for checking upstream connection. For this purpose new parameter trusted_server_command is introduced.
* 3.3.5:  [http://www.pgpool.net/docs/pgpool-II-3.3.5/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.5/doc/pgpool-ja.html#release3.3.5 Japanese]
 
* 3.2.10:  [http://www.pgpool.net/docs/pgpool-II-3.2.10/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.10/doc/pgpool-ja.html#release3.2.10 Japanese]
 
* 3.1.13: [http://www.pgpool.net/docs/pgpool-II-3.1.13/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.13/doc/pgpool-ja.html#release3.1.13 Japanese]
 
* 3.0.17: [http://www.pgpool.net/docs/pgpool-II-3.0.17/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.0.17/doc/pgpool-ja.html#release3.0.17 Japanese]
 
  
* pgpoolAdmin 3.4.1: [http://www.pgpool.net/docs/pgpoolAdmin-3.4.1/NEWS.txt English]
+
* Import PostgreSQL 15's SQL parser.
  
=== The pgpool-II official yum repository released (2014/12/16) ===
+
* Speed up query cache by reducing lock contention. This allows concurrent running clients to fetch cache contents much more quicker.
  
PgPool Global Development Group announced the pgpool-II official yum repository.  
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
With this repository, you will be able to install or update pgpool-II and pgpoolAdmin etc. by using yum.
 
  
http://www.pgpool.net/yum/
+
Release notes:
 +
[https://www.pgpool.net/docs/44/en/html/release-4-4-0.html English]
  
The yum repository currently supports pgpool-II 3.3 or above with RHEL6 x86_64.
+
=== Pgpool-II 4.3 RC1 released (2021/11/25) ===
  
See [[Yum Repository]] for detail.
+
Pgpool-II 4.3 RC1 is now released. Please take a look at [https://www.pgpool.net/docs/43/en/html/release-4-3rc1.html 4.3 RC1]
  
=== pgpool-II 3.4.0 and pgpoolAdmin 3.4.0 officially released (2014/11/07) ===
+
Note that this is not a stable version but just for developers.
  
Pgpool-II 3.4.0 is now officially released.
+
V4.3 contains new features and enhancements, including:
 +
* A new membership mechanism is introduced to Watchdog to allow to keep quorum/VIP when some of watchdog nodes are removed.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Allow to choose the least replication delay standby node when selecting the load balance node.  
  
 +
* Allow to specify the node id to be promoted in pcp_promote_node.
  
V3.4's new features are:
+
* Allow to configure to not trigger failover when PostgreSQL is shutdown by admin or killed by pg_terminate_backend.  
  
* Allow fine control of load balancing by using application name or database name
+
* Add new fields to pcp_proc_info, SHOW POOL_PROCESSES and SHOW POOL_POOLS command to display more useful information to admin.
* New features about log output
 
** Allow to print pgpool-II process names
 
**  Allow to control log verbosity like PostgreSQL
 
* SQL parser compatible with PostgreSQL 9.4
 
* Import PostgreSQL's memory manager and exception manager
 
* Support IPv6 address
 
* Reorganize source code tree
 
* etc.  
 
  
 +
* Allow pcp_node_info to list all backend nodes information.
  
* 3.4.0 release note:  [http://www.pgpool.net/docs/pgpool-II-3.4.0/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.4.0/doc/pgpool-ja.html#release3.4.0 Japanese]
+
* Add new fields showing actual PostgreSQL status to SHOW POOL NODES command and friends.
  
=== pgpool-II 3.3.4, 3.2.9, 3.1.12, and 3.0.16 are officially released (2014/09/05) ===
+
* Add a new parameter which represents the recovery source hostname to recovery_1st_stage_command and recovery_2nd_stage_command.  
  
These are the latest stable versions of each major branches.  
+
* Add support for log time stamp with milliseconds.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Import PostgreSQL 14's SQL parser.
  
* 3.3.4:  [http://www.pgpool.net/docs/pgpool-II-3.3.4/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.4/doc/pgpool-ja.html#release3.3.4 Japanese]
+
* Support include directive in pgppol.conf file. You can have separate sub-config file to be included in pgpool.conf.
* 3.2.9:  [http://www.pgpool.net/docs/pgpool-II-3.2.9/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.9/doc/pgpool-ja.html#release3.2.9 Japanese]
 
* 3.1.12: [http://www.pgpool.net/docs/pgpool-II-3.1.12/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.12/doc/pgpool-ja.html#release3.1.12 Japanese]
 
* 3.0.16: [http://www.pgpool.net/docs/pgpool-II-3.0.16/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.0.16/doc/pgpool-ja.html#release3.0.16 Japanese]
 
  
=== pgpool-ha 2.2 released (2014/04/01) ===
+
* pgpool.conf sample files are unified into single sample file for easier configuration.
  
This is the latest stable version.
+
* All configuration parameters in pgpool.conf sample file are commented out to clarify which parameter is needed to be changed.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads#pgpool-HA here].
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
  
 +
Release notes:
 +
[https://www.pgpool.net/docs/43/en/html/release-4-3-0.html English]
  
=== pgpool-II 3.3.3, 3.2.8, 3.1.11, 3.0.15  and pgpoolAdmin 3.3.1 officially released (2014/03/24) ===
 
  
These are the latest stable versions of each major branches.  
+
=== Pgpool-II 4.3 beta2 released (2021/11/18) ===
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
Pgpool-II 4.3 beta2 is now released. Please take a look at [https://www.pgpool.net/docs/43/en/html/release-4-3beta2.html 4.3 beta2]
  
* 3.3.3:  [http://www.pgpool.net/docs/pgpool-II-3.3.3/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.3/doc/pgpool-ja.html#release3.3.3 Japanese]
+
Note that this is not a stable version but just for developers.
* 3.2.8:  [http://www.pgpool.net/docs/pgpool-II-3.2.8/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.8/doc/pgpool-ja.html#release3.2.8 Japanese]
 
* 3.1.11: [http://www.pgpool.net/docs/pgpool-II-3.1.11/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.11/doc/pgpool-ja.html#release3.1.11 Japanese]
 
* 3.0.15: [http://www.pgpool.net/docs/pgpool-II-3.0.15/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.0.15/doc/pgpool-ja.html#release3.0.15 Japanese]
 
  
* pgpoolAdmin 3.3.1: [http://www.pgpool.net/docs/pgpoolAdmin-3.3.1/NEWS.txt English]
+
V4.3 contains new features and enhancements, including:
 +
* A new membership mechanism is introduced to Watchdog to allow to keep quorum/VIP when some of watchdog nodes are removed.
  
=== pgpool-II 3.2.7, 3.1.10, 3.0.14 officially released (2013/12/06) ===
+
* Allow to choose the least replication delay standby node when selecting the load balance node.  
  
These are the latest stable versions of each major branches.  
+
* Allow to specify the node id to be promoted in pcp_promote_node.  
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Allow to configure to not trigger failover when PostgreSQL is shutdown by admin or killed by pg_terminate_backend.  
  
* 3.2.7:  [http://www.pgpool.net/docs/pgpool-II-3.2.7/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.2.7/doc/pgpool-ja.html#release3.2.7 Japanese]
+
* Add new fields to pcp_proc_info, SHOW POOL_PROCESSES and SHOW POOL_POOLS command to display more useful information to admin.
* 3.1.10: [http://www.pgpool.net/docs/pgpool-II-3.1.10/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.1.10/doc/pgpool-ja.html#release3.1.10 Japanese]
 
* 3.0.14: [http://www.pgpool.net/docs/pgpool-II-3.0.14/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.0.14/doc/pgpool-ja.html#release3.0.14 Japanese]
 
  
=== pgpool-II 3.3.2 officially released (2013/11/29) ===
+
* Allow pcp_node_info to list all backend nodes information.
  
These are the latest stable version of 3.3.
+
* Add new fields showing actual PostgreSQL status to SHOW POOL NODES command and friends.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Add a new parameter which represents the recovery source hostname to recovery_1st_stage_command and recovery_2nd_stage_command.  
  
* 3.3.2: [http://www.pgpool.net/docs/pgpool-II-3.3.2/NEWS.txt English] [http://www.pgpool.net/docs/pgpool-II-3.3.2/doc/pgpool-ja.html#release3.0.7 Japanese]
+
* Add support for log time stamp with milliseconds.
  
=== pgpool-II 3.3.1, 3.2.6, 3.1.9, 3.0.13 officially released (2013/09/06) ===
+
* Import PostgreSQL 14's SQL parser.
  
These are the latest stable versions of each major branches.  
+
* Support include directive in pgppol.conf file. You can have separate sub-config file to be included in pgpool.conf.
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* pgpool.conf sample files are unified into single sample file for easier configuration.
  
=== Missing regression test suite in pgpool-II 3.3.0.tar.gz (2013/07/31) ===
+
* All configuration parameters in pgpool.conf sample file are commented out to clarify which parameter is needed to be changed.
  
New regression test suite was not accidentally included in the pgpool-II 3.3.0.tar.gz tar ball.
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
You can get it from git repository or download from
 
[http://www.pgpool.net/download.php?f=regression-3.3.0.tar.gz here].
 
  
=== pgpool-II 3.3 and pgpoolAdmin 3.3 officially released (2013/07/30) ===
+
Release notes:
 +
[https://www.pgpool.net/docs/43/en/html/release-4-3-0.html English]
  
Pgpool-II 3.3 is now officially released.
+
=== Pgpool-II 4.3 beta1 released (2021/11/09) ===
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
Pgpool-II 4.3 beta1 is now released.  
  
V3.3's new features are:
+
Note that this is not a stable version but just for developers.
  
* Enhancements for watchdog
+
V4.3 contains new features and enhancements, including:
** New monitoring method of watchdog lifecheck using heartbeat signal
+
* A new membership mechanism is introduced to Watchdog to allow to keep quorum/VIP when some of watchdog nodes are removed.
** Interlocking of failover/failback script
 
** Secure watchdog communication
 
** PCP command for retrieving the watchdog status
 
** etc.
 
* Othres
 
** Import PostgreSQL 9.2 raw parser
 
** New pgpool_setup tool
 
** Support for using CREATE EXTENSION to install pgpool specific extensions
 
** regression test suit
 
** etc.  
 
  
* [http://www.pgpool.net/docs/pgpool-II-3.3.0/NEWS.txt pgpool-II 3.3 release note (English)]
+
* Allow to choose the least replication delay standby node when selecting the load balance node.  
* [http://www.pgpool.net/docs/pgpool-II-3.3.0/pgpool-ja.html#release3.3.0 pgpool-II 3.3 release note (Japanese)]
 
  
=== pgpool-II 3.2.5, 3.1.8, 3.0.12 officially released (2013/07/10) ===
+
* Allow to specify the node id to be promoted in pcp_promote_node.  
  
These are the latest stable versions of each major branches.  
+
* Allow to configure to not trigger failover when PostgreSQL is shutdown by admin or killed by pg_terminate_backend.  
  
You can download them [http://pgpool.net/mediawiki/index.php/Downloads here].
+
* Add new fields to pcp_proc_info, SHOW POOL_PROCESSES and SHOW POOL_POOLS command to display more useful information to admin.
  
== Development ==
+
* Allow pcp_node_info to list all backend nodes information.
 +
 
 +
* Add new fields showing actual PostgreSQL status to SHOW POOL NODES command and friends.
 +
 
 +
* Add a new parameter which represents the recovery source hostname to recovery_1st_stage_command and recovery_2nd_stage_command.
 +
 
 +
* Add support for log time stamp with milliseconds.
 +
 
 +
* Import PostgreSQL 14's SQL parser.
  
=== Pgpool-II 3.7 RC1 and pgpoolAdmin 3.7 RC1 released (2017/11/13) ===
+
* Support include directive in pgppol.conf file. You can have separate sub-config file to be included in pgpool.conf.
  
Pgpool-II 3.7 RC1 and pgpoolAdmin 3.7 RC1 are now relased.
+
* pgpool.conf sample files are unified into single sample file for easier configuration.
This is not intended to be used in production but is close to the
 
release version. So users are encouraged to test it out.
 
  
V3.7 has new features:
+
* All configuration parameters in pgpool.conf sample file are commented out to clarify which parameter is needed to be changed.
* Quorum aware failover feature.
 
* Allow specifying the hostnames in pool_hba.
 
* Allow to specify per node health check parameters.
 
* Support AWS Aurora.
 
* Import PostgreSQL 10 SQL parser.
 
* Support logical replication.
 
* etc.
 
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
  
 
Release notes:
 
Release notes:
[http://www.pgpool.net/docs/pgpool-II-3.7.0/doc/en/html/release-3-7.html English] [http://www.pgpool.net/docs/pgpool-II-3.7.0/doc/ja/html/release-3-7.html Japanese]
+
[https://www.pgpool.net/docs/43/en/html/release-4-3-0.html English]
 +
 
 +
=== Pgpool-II 4.2 beta1 released (2020/10/27) ===
 +
 
 +
Pgpool-II 4.2 beta1 is now released.  
 +
 
 +
Note that this is not a stable version but just for developers.
 +
 
 +
V4.2 contains new features and enhancements, including:
  
=== Pgpool-II 3.7 beta1 released (2017/10/17) ===
+
* Some items in the configuration file pgpool.conf are vastly enhanced for easier configuration and administration.
  
Pgpool-II 3.7 beta1 is now relased. This is not a stable version but just for developers.
+
* Implement logging_collector for easier log management.
  
V3.7 has new features:
+
* Implement log_disconnections to collect disconnection logs.
* Quorum aware failover feature.
+
 
* Allow specifying the hostnames in pool_hba.
+
* Implement pg_enc and pg_md5 to allow to register multiple passwords at once.
* Allow to specify per node health check parameters.
+
 
* Support AWS Aurora.
+
* Allow to show statistics of health check by using SHOW POOL_HEALTH_CHECK_STATS command, and also allow to show statistics of issued SQL by using SHOW POOL_BACKEND_STATS command.
* Import PostgreSQL 10 SQL parser.
+
 
* Support logical replication.
+
* New PCP command pcp_reload_config is added.
* etc.
+
 
 +
* Now it is possible to omit write_function_list and read_only_function_list by looking at system catalog information.
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
* Add new clustering mode snapshot_isolation_mode which guarantees not only data modifications to multiple PostgreSQL but read consistency.
  
=== pgpool-II 3.6 RC1 released (2016/11/16) ===
+
* Support LDAP authentication between clients and Pgpool-II.
  
pgpool-II 3.6 RC1 is now relased. This is not a stable version but just for developers.
+
* Add ssl_crl_file and ssl_passphrase_command to SSL configuration.
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
* Import PostgreSQL 13's SQL parser.  
  
=== pgpool-II 3.6 beta2 released (2016/11/08) ===
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
  
pgpool-II 3.6 beta2 is now relased. This is not a stable version but just for developers.
+
Release notes:
 +
[https://www.pgpool.net/docs/42/en/html/release-4-2-0.html English]
  
Users are encouraged to take part in our beta test program. Please help us in testing and making pgpool-II 3.6 better!
+
=== Pgpool-II 4.2 alpha1 released (2020/10/06) ===
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
Pgpool-II 4.2 alpha1 is now released.  
  
=== pgpool-II 3.6 beta1 released (2016/11/02) ===
+
Note that this is not a stable version but just for developers.
  
pgpool-II 3.6 beta1 is now relased. This is not a stable version but just for developers.
+
V4.2 contains new features and enhancements, including:
  
Users are encouraged to take part in our beta test program. Please help us in testing and making pgpool-II 3.6 better!
+
* Some items in the configuration file pgpool.conf are vastly enhanced for easier configuration and administration.
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
* Implement logging_collector for easier log management.
  
=== Pgpool-II 3.6 alpha1 released (2016/10/19) ===
+
* Implement log_disconnections to collect disconnection logs.
  
Pgpool-II 3.6 alpha1 is now relased. This is not a stable version but just for developers.
+
* Implement pg_enc and pg_md5 to allow to register multiple passwords at once.
  
V3.6 has a new feature:
+
* Allow to show statistics of health check by using SHOW POOL_HEALTH_CHECK_STATS command, and also allow to show statistics of issued SQL by using SHOW POOL_BACKEND_STATS command.
* Improve the behavior of fail-over.
 
* New PGPOOL SET command has been introduced.
 
* Watchdog is significantly enhanced.
 
* 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.
 
* etc.
 
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
* New PCP command pcp_reload_config is added.
  
=== pgpool-II 3.5 RC1 released (2016/1/14) ===
+
* Now it is possible to omit write_function_list and read_only_function_list by looking at system catalog information.
  
pgpool-II 3.5 RC1 and pgpoolAdmin 3.5 RC1 are now relased. This is not a stable version but just for developers.
+
* Add new clustering mode snapshot_isolation_mode which guarantees not only data modifications to multiple PostgreSQL but read consistency.
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
* Support LDAP authentication between clients and Pgpool-II.
  
=== pgpool-II 3.5 beta1 released (2015/12/14) ===
+
* Add ssl_crl_file and ssl_passphrase_command to SSL configuration.
  
pgpool-II 3.5 beta1 and pgpoolAdmin 3.5 beta1 are now relased. This is not a stable version but just for developers.
+
* Import PostgreSQL 13's SQL parser.  
  
Users are encouraged to take part in our beta test program. Please help us in testing and making pgpool-II 3.5 better!
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
Release notes:
 +
[https://www.pgpool.net/docs/42/en/html/release-4-2-0.html English]
  
=== pgpool-II 3.5 alpha1 released (2015/11/16) ===
+
=== Pgpool-II 4.1 RC1 released (2019/10/16) ===
  
Pgpool-II 3.5 alpha1 is now relased. This is not a stable version but just for developers.
+
Pgpool-II 4.1 RC1 is now released.  
  
V3.5 has a new feature:
+
This is not intended to be used in production but is close to the release version. So users are encouraged to test it out.  
* Improved performance in extended query protocol
 
* Overcoming the thundering herd problem
 
* watchdog feature enhancements to be more robust and adaptable
 
* PCP command enhancements
 
* Import PostgreSQL 9.5 parser
 
* etc.
 
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
 
  
 +
Major enhancements in Pgpool-II 4.1 include:
  
=== pgpool-II 3.3 RC1 released (2013/07/25) ===
+
* Statement level load balancing.
 +
* Auto failback.
 +
* Enhance performance in number of areas.
 +
** Shared relation cache allows to reuse relation cache among sessions to reduce internal queries against PostgreSQL system catalogs.
 +
** Have separate SQL parser for DML statements to eliminate unnecessary parsing effort.
 +
** Load balancing control for specific queries.
 +
* Reduce Internal Queries against System Catalogs.
 +
* Import PostgreSQL 12 SQL parser.
 +
* etc.
  
Pgpool-II 3.3 RC1 is now relased. This is not a stable version but just for developers.
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
Release notes:
 +
[https://www.pgpool.net/docs/41/en/html/ English]
  
=== pgpool-II 3.3 beta1 released (2013/06/12) ===
+
=== Pgpool-II 4.1 beta1 released (2019/09/06) ===
  
Pgpool-II 3.3 beta1 is now relased. This is not a stable version but just for developers.
+
Pgpool-II 4.1 beta1 is now released.  
  
Users are encouraged to take part in our beta test program. Please help us in testing and making pgpool-II 3.3 better!
+
This is not a stable version but just for developers.
  
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
+
Major enhancements in Pgpool-II 4.1 include:
  
=== pgpool-II 3.3 alpha1 released (2013/05/17) ===
+
* Statement level load balancing.
 +
* Auto failback.
 +
* Enhance performance in number of areas.
 +
** Shared relation cache allows to reuse relation cache among sessions to reduce internal queries against PostgreSQL system catalogs.
 +
** Have separate SQL parser for DML statements to eliminate unnecessary parsing effort.
 +
** Load balancing control for specific queries.
 +
* Reduce Internal Queries against System Catalogs.
 +
* Import PostgreSQL 12 SQL parser.
 +
* etc.
  
Pgpool-II 3.3 alpha1 is now relased. This is not a stable version but just for developers.
+
You can download it from [https://pgpool.net/mediawiki/index.php/Developer_releases here].
  
V3.3 has a new feature:
+
Release notes:
* Enhancements for watchdog
+
[https://www.pgpool.net/docs/41/en/html/ English]
** New monitoring method of watchdog lifecheck using heartbeat signal
 
** Interlocking of failover/failback script
 
** Secure watchdog communication
 
** etc.
 
* Othres
 
** Import PostgreSQL 9.2 raw parser
 
** New pgpool_setup tool
 
** Support for using CREATE EXTENSION to install pgpool specific extensions
 
You can download it from [http://pgpool.net/mediawiki/index.php/Developer_releases here].
 
  
 
== Old ==
 
== Old ==
 
See [[Old news|this page]].
 
See [[Old news|this page]].
  
= Where can I get commercial support for pgpool-II? =
+
= Where can I get commercial support for Pgpool-II? =
  
Some commercial packages include pgpool-II support. Consulting and annual support can be purchased from SRA OSS, Inc. Japan (http://www.sraoss.co.jp/index_en.php).
+
Some commercial packages include Pgpool-II support. Consulting and annual support can be purchased from SRA OSS LLC (https://www.sraoss.co.jp/index_en.php).

Revision as of 00:49, 29 February 2024


Contents

Welcome to Pgpool Wiki!

What is Pgpool-II?

Pgpool-II is a middleware that works between PostgreSQL servers and a PostgreSQL database client. It is distributed under a license similar to BSD and MIT. It provides the following features.

  • Connection Pooling
Pgpool-II saves connections to the PostgreSQL servers, and reuse them whenever a new connection with the same properties (i.e. username, database, protocol version) comes in. It reduces connection overhead, and improves system's overall throughput.
  • Replication
Pgpool-II can manage multiple PostgreSQL servers. Using the replication function enables creating a realtime backup on 2 or more physical disks, so that the service can continue without stopping servers in case of a disk failure.
  • Load Balancing
If a database is replicated, executing a SELECT query on any server will return the same result. Pgpool-II takes an advantage of the replication feature to reduce the load on each PostgreSQL server by distributing SELECT queries among multiple servers, improving system's overall throughput. At best, performance improves proportionally to the number of PostgreSQL servers. Load balance works best in a situation where there are a lot of users executing many queries at the same time.
  • Limiting Exceeding Connections
There is a limit on the maximum number of concurrent connections with PostgreSQL, and connections are rejected after this many connections. Setting the maximum number of connections, however, increases resource consumption and affect system performance. pgpool-II also has a limit on the maximum number of connections, but extra connections will be queued instead of returning an error immediately.
  • Watchdog
Watchdog can coordinate multiple Pgpool-II, create a robust cluster system and avoid the single point of failure or split brain. Watchdog can perform lifecheck against other pgpool-II nodes, to detect a fault of Pgpoll-II. If active Pgpool-II goes down, standby Pgpool-II can be promoted to active, and take over Virtual IP.
  • In Memory Query Cache
In memory query cache allows to save a pair of SELECT statement and its result. If an identical SELECTs comes in, Pgpool-II returns the value from cache. Since no SQL parsing nor access to PostgreSQL are involved, using in memory cache is extremely fast. On the other hand, it might be slower than the normal path in some cases, because it adds some overhead of storing cache data.

Pgpool-II speaks PostgreSQL's backend and frontend protocol, and relays messages between a backend and a frontend. Therefore, a database application (frontend) thinks that Pgpool-II is the actual PostgreSQL server, and the server (backend) sees Pgpool-II as one of its clients. Because Pgpool-II is transparent to both the server and the client, an existing database application can be used with Pgpool-II almost without a

Pgpool-II talks PostgreSQL's backend and frontend protocol, and relays a connection between them. Therefore, a database application (frontend) thinks that Pgpool-II is the actual PostgreSQL server, and the server (backend) sees Pgpool-II as one of its clients. Because Pgpool-II is transparent to both the server and the client, an existing database application can be used with Pgpool-II almost without a change to its sources.

Pgpool-II License

See License.

Stable versions

  • Pgpool-II: 4.5, 4.4, 4.3, 4.2, 4.1

Contacts

  • If you have technical questions regarding Pgpool-II, please subscribe Pgpool-II mailing lists and send questions to it (pgpool-general will be a starter). Please do not send technical questions via private email. We will not respond such that messages.
  • If you believe that you found a vulnerability/security issues with Pgpool-II, please send a private email to ishii at sraoss.co.jp (he is the project leader).

What's new

News

Pgpool-II 4.5.1, 4.4.6, 4.3.9, 4.2.16 and 4.1.19 officially released (2024/02/29)

Pgpool-II 4.5.1, 4.4.6, 4.3.9, 4.2.16 and 4.1.19 officially released.

You can download them here.

Events

PGConf.ASIA 2019 in Bali

Bo Peng is going to give a presentation Setup a High-Availability and Load Balancing PostgreSQL Cluster: New Features of Pgpool-II 4.1 at "PGConf.ASIA 2019" held in Bali from September 8th to 11st.

PGConf.ASIA 2018 in Tokyo

Tatsuo Ishii and Bo Peng are going to give a presentation Celebrating its 15th Anniversary Pgpool-II Past Present and Future Celebrating its 15th Anniversary Pgpool-II Past Present and Future part2 at "PGConf.ASIA 2018" held in Tokyo from December 10th to 12th.

PGConf.ASIA 2017 in Tokyo

Tatsuo Ishii is going to give a presentation "More reliability and support for PostgreSQL 10: Introducing Pgpool-II 3.7" at "PGConf.ASIA 2017", held in Tokyo from December 4th to 6th.

PostgreSQL Conference in Russia 2016

Tatsuo gave a talk "How to manage a herd of elephants" at "PostgreSQL Conference in Russia 2016", held in Moscow from February 4th to 5th. The slides are available in Developer's documentation.

PostgreSQL Conference in China 2015

Tatsuo gave a talk "How to manage a herd of elephants" at "PostgreSQL Conference in China 2015", held in Beijing from November 21th to 22th. The slides are available in Developer's documentation.

pgCon 2015 Cluster Hacker Summit

We participated "6th Postgres Cluster Hacker Summit" which was held as a part of PgCon 2015 Developer Unconference. We reported about Development Status Updates and pgpool-II 3.5 features. The slides are available in Developer's documentation.

Pgpool-II Day 2015 in Tokyo

We had the very first time pgpool-II decicated conference. See the event report.

Stable

Pgpool-II 4.5.1, 4.4.6, 4.3.9, 4.2.16 and 4.1.19 officially released (2024/02/29)

Pgpool-II 4.5.1, 4.4.6, 4.3.9, 4.2.16 and 4.1.19 officially released.

You can download them here.

Pgpool-II 4.5.0 released (2023/12/12)

Pgpool-II 4.5.0 is now released. This is the first stable release of Pgpool-II 4.5.x.

V4.5 contains new features and enhancements, including:

  • Allow to use more kind of multiple statements in a query string.
  • Allow to load balance PREPARE/EXECUTE/DEALLOCATE.
  • Allow to set delay_threshold_by_time in milliseconds.
  • Avoid session disconnection issue in failover/failback/backend error in some cases.
  • Allow to route queries to a specific backend node for a specific user connection.
  • Support multiple directories specification for pcp_socket_dir.
  • Import PostgreSQL 16's SQL parser.

You can download it from here.

Release notes: English

Pgpool-II 4.4.5, 4.3.8, 4.2.15, 4.1.18 and 4.0.25 officially released (2023/11/30)

Pgpool-II 4.4.5, 4.3.8, 4.2.15, 4.1.18 and 4.0.25 officially released.

Please note that 4.0.25 is the last release of the 4.0.x series.

You can download them here.

Pgpool-II 4.4.4, 4.3.7, 4.2.14, 4.1.17 and 4.0.24 officially released (2023/08/17)

Pgpool-II 4.4.4, 4.3.7, 4.2.14, 4.1.17 and 4.0.24 officially released.

You can download them here.

Pgpool-II 4.4.3, 4.3.6, 4.2.13, 4.1.16 and 4.0.23 officially released (2023/05/18)

Pgpool-II 4.4.3, 4.3.6, 4.2.13, 4.1.16 and 4.0.23 officially released.

You can download them here.

End-of-Life (EOL) Announcement for pgpoolAdmin (2023/02/17)

Pgpool Global Development Group announces end-of-life date for pgpoolAdmin, which is the management tool for Pgpool-II.

Pgpool Global Development Group will provide maintenance for pgpoolAdmin 4.0, 4.1 and 4.2 until December 31, 2023. After this date, bug fixes and security fixes for these versions will no longer be provided.

In addition, pgpoolAdmin for Pgpool-II 4.3 or later will not be released.

We would like to thank you for using pgpoolAdmin over the years.

Pgpool-II 4.4.2, 4.3.5, 4.2.12, 4.1.15 and 4.0.22 officially released (2023/01/23)

Pgpool-II 4.4.2, 4.3.5, 4.2.12, 4.1.15 and 4.0.22 officially released.

This release contains a security fix.

If following conditions are all met, the password of "wd_lifecheck_user" is exposed by "SHOW POOL STATUS" command. The command can be executed by any user who can connect to Pgpool-II. (CVE-2023-22332)

  • Version 3.3 or later
  • use_watchdog = on
  • wd_lifecheck_method = 'query'
  • A plain text password is set to wd_lifecheck_password

In this case it is strongly recommended to upgrade to this version (we do not expose wd_lifecheck_password in show pool_status command any more), or use one of following workarounds.

Workarounds for 4.0.x to 4.4.x users:

  • Disable watchdog. Set use_watchdog to off.
  • Change wd_lifecheck_method to heartbeat.
  • Set an empty string to wd_lifecheck_password. This will use password in the pool_passwd file.
  • Set an AES encrypted password to wd_lifecheck_password.

In any case we recommend to change "wd_lifecheck_password" in PostgreSQL.

Workarounds for 3.0.x to 3.7.x users:

  • Disable watchdog. Set use_watchdog to off.
  • Change wd_lifecheck_method to heartbeat.

In any case we recommend to change "wd_lifecheck_password" in PostgreSQL.

Please note that Pgpool-II 3.7.x or before are end of life and no minor updates are provided for those versions.

You can download them here.

Pgpool-II 4.4.1, 4.3.4, 4.2.11, 4.1.14, 4.0.21 and 3.7.26 officially released (2022/12/22)

Pgpool-II 4.4.1, 4.3.4, 4.2.11, 4.1.14, 4.0.21 and 3.7.26 officially released.

You can download them here.

Pgpool-II 4.4.0 released (2022/12/06)

Pgpool-II 4.4.0 is now released. This is the first stable release of Pgpool-II 4.4.x.

V4.4 contains new features and enhancements, including:

  • Add new dynamic spare process management feature. This feature allows selecting between static and dynamic process management modes.
  • Allow to specify replication delay by time in streaming replication mode. For this purpose new parameter delay_threshold_by_time is introduced.
  • As PostgreSQL already does, Pgpool-II now supports unix_socket_directories, unix_socket_group and unix_socket_permissions for more flexible and precise control of UNIX domain sockets.
  • Allow to use comma separated multiple listen addresses in listen_addresses and pcp_listen_addresses. They control which interfaces accept connection attempts, which can help prevent repeated malicious connection requests on insecure network interfaces.
  • Allow to customize the command used by trusted_servers for checking upstream connection. For this purpose new parameter trusted_server_command is introduced.
  • Import PostgreSQL 15's SQL parser.
  • Speed up query cache by reducing lock contention. This allows concurrent running clients to fetch cache contents much more quicker.

You can download it from here.

Release notes: English Japanese

Pgpool-II 4.3.3, 4.2.10, 4.1.13, 4.0.20 and 3.7.25 officially released (2022/08/18)

Pgpool-II 4.3.3, 4.2.10, 4.1.13, 4.0.20 and 3.7.25 officially released.

You can download them here.

Pgpool-II 4.3.2, 4.2.9, 4.1.12, 4.0.19 and 3.7.24 officially released (2022/05/19)

Pgpool-II 4.3.2, 4.2.9, 4.1.12, 4.0.19 and 3.7.24 officially released.

You can download them here.

Pgpool-II 4.3.1, 4.2.8, 4.1.11, 4.0.18 and 3.7.23 officially released (2022/02/17)

Pgpool-II 4.3.1, 4.2.8, 4.1.11, 4.0.18 and 3.7.23 officially released.

You can download them here.

Pgpool-II 4.2.7, 4.1.10, 4.0.17 and 3.7.22 officially released (2021/12/23)

Pgpool-II 4.2.7, 4.1.10, 4.0.17 and 3.7.22 officially released.

The purpose of this release is to provide packages for PostgreSQL 14.

You can download them here.

Pgpool-II 4.3.0 released (2021/12/07)

Pgpool-II 4.3.0 is now released. Please take a look at 4.3.0

V4.3.0 contains new features and enhancements, including:

  • A new membership mechanism is introduced to Watchdog to allow to keep quorum/VIP when some of watchdog nodes are removed.
  • Allow to choose the least replication delay standby node when selecting the load balance node.
  • Allow to specify the node id to be promoted in pcp_promote_node.
  • Allow to configure to not trigger failover when PostgreSQL is shutdown by admin or killed by pg_terminate_backend.
  • Add new fields to pcp_proc_info, SHOW POOL_PROCESSES and SHOW POOL_POOLS command to display more useful information to admin.
  • Allow pcp_node_info to list all backend nodes information.
  • Add new fields showing actual PostgreSQL status to SHOW POOL NODES command and friends.
  • Add a new parameter which represents the recovery source hostname to recovery_1st_stage_command and recovery_2nd_stage_command.
  • Add support for log time stamp with milliseconds.
  • Import PostgreSQL 14's SQL parser.
  • Support include directive in pgppol.conf file. You can have separate sub-config file to be included in pgpool.conf.
  • pgpool.conf sample files are unified into single sample file for easier configuration.
  • All configuration parameters in pgpool.conf sample file are commented out to clarify which parameter is needed to be changed.

You can download it from here.

Release notes: English

Pgpool-II 4.2.6, 4.1.9, 4.0.16, 3.7.21 and 3.6.28 officially released (2021/11/18)

Pgpool-II 4.2.6, 4.1.9, 4.0.16, 3.7.21 and 3.6.28 officially released.

You can download them here.

Pgpool-II 4.2.5 released (2021/09/14)

Pgpool Global Development Group is pleased to announce the availability of Pgpool-II 4.2.5.

You can download them here.

Pgpool-II 4.2.4, 4.1.8, 4.0.15, 3.7.20 and 3.6.27 officially released (2021/08/05)

Pgpool-II 4.2.4, 4.1.8, 4.0.15, 3.7.20 and 3.6.27 officially released.

You can download them here.

pgpoolAdmin 4.2.0 officially released (2021/06/17)

pgpoolAdmin 4.2.0 officially released.

pgpoolAdmin 4.2.0 adds support for Pgpool-II 4.2. Please take a look at release notes.

You can download them here.

Pgpool-II 4.2.3, 4.1.7, 4.0.14, 3.7.19 and 3.6.26 officially released (2021/05/20)

Pgpool-II 4.2.3, 4.1.7, 4.0.14, 3.7.19 and 3.6.26 officially released.

You can download them here.

Pgpool-II 4.2.2, 4.1.6, 4.0.13, 3.7.18 and 3.6.25 officially released (2021/02/18)

Pgpool-II 4.2.2, 4.1.6, 4.0.13, 3.7.18 and 3.6.25 officially released.

You can download them here.

Pgpool-II 4.2.1 released (2020/12/23)

Pgpool-II 4.2.1 is now released.

You can download them from here.

Pgpool-II 4.2.0 released (2020/11/26)

Pgpool-II 4.2.0 is now released.

V4.2 contains new features and enhancements, including:

  • Some items in the configuration file pgpool.conf are vastly enhanced for easier configuration and administration.
  • Implement logging_collector for easier log management.
  • Implement log_disconnections to collect disconnection logs.
  • Implement pg_enc and pg_md5 to allow to register multiple passwords at once.
  • Allow to show statistics of health check by using SHOW POOL_HEALTH_CHECK_STATS command, and also allow to show statistics of issued SQL by using SHOW POOL_BACKEND_STATS command.
  • New PCP command pcp_reload_config is added.
  • Now it is possible to omit write_function_list and read_only_function_list by looking at system catalog information.
  • Add new clustering mode snapshot_isolation_mode which guarantees not only data modifications to multiple PostgreSQL but read consistency.
  • Support LDAP authentication between clients and Pgpool-II.
  • Add ssl_crl_file and ssl_passphrase_command to SSL configuration.
  • Import PostgreSQL 13's SQL parser.

You can download it from here.

Release notes: English

Pgpool-II 4.1.5, 4.0.12, 3.7.17, 3.6.24 and 3.5.28 officially released (2020/11/19)

Pgpool-II 4.1.5, 4.0.12, 3.7.17, 3.6.24 and 3.5.28 officially released

You can download them here.

Pgpool-II 4.1.4, 4.0.11, 3.7.16, 3.6.23 and 3.5.27 officially released (2020/09/17)

Pgpool-II 4.1.4, 4.0.11, 3.7.16, 3.6.23 and 3.5.27 officially released

You can download them here.

Pgpool-II 4.1.3, 4.0.10, 3.7.15, 3.6.22 and 3.5.26 officially released (2020/08/20)

Pgpool-II 4.1.3, 4.0.10, 3.7.15, 3.6.22 and 3.5.26 officially released

You can download them here.

Pgpool-II 4.1.2, 4.0.9, 3.7.14, 3.6.21 and 3.5.25 officially released (2020/05/21)

Pgpool-II 4.1.2, 4.0.9, 3.7.14, 3.6.21 and 3.5.25 officially released

You can download them here.

Pgpool-II 4.1.1, 4.0.8, 3.7.13, 3.6.20, 3.5.24 and pgpoolAdmin 4.1.0 officially released (2020/02/20)

Pgpool-II 4.1.1, 4.0.8, 3.7.13, 3.6.20, 3.5.24 and pgpoolAdmin 4.1.0 officially released

You can download them here.

Pgpool-II 4.1.0, 4.0.7, 3.7.12, 3.6.19, 3.5.23 and 3.4.26 RPMs Update 2 officially released (2019/11/19)

Pgpool-II 4.1.0, 4.0.7, 3.7.12, 3.6.19, 3.5.23 and 3.4.26 RPMs Update 2 are officially released. The updated RPM packages fixed the bug which logs are not output, when log_destination = 'syslog' is configured.

You can download them here.

Pgpool-II 4.1.0 released (2019/10/31)

Pgpool-II 4.1.0 is now relased.

Major enhancements in Pgpool-II 4.1 include:

  • Statement level load balancing.
  • Auto failback.
  • Enhance performance in number of areas.
    • Shared relation cache allows to reuse relation cache among sessions to reduce internal queries against PostgreSQL system catalogs.
    • Have separate SQL parser for DML statements to eliminate unnecessary parsing effort.
    • Load balancing control for specific queries.
  • Reduce Internal Queries against System Catalogs.
  • Import PostgreSQL 12 SQL parser.
  • etc.

You can download it from here.

Release notes: English Japanese

Development

Pgpool-II 4.5 RC1 released (2023/11/28)

Pgpool-II 4.5 RC1 is now released.

Note that this is not a stable version but just for developers.

V4.5 contains new features and enhancements, including:

  • Allow to use multiple statements in a query string.
  • Allow to set delay_threshold_by_time in milliseconds.
  • Avoid session disconnection issue in failover/failback/backend error in some cases.
  • Allow to route queries to a specific backend node for a specific user connection.
  • Support multiple directories specification for pcp_socket_dir.
  • Import PostgreSQL 16's SQL parser.

You can download it from here.

Release notes: English

Pgpool-II 4.5 beta1 released (2023/11/14)

Pgpool-II 4.5 beta1 is now released.

Note that this is not a stable version but just for developers.

V4.5 contains new features and enhancements, including:

  • Allow to use multiple statements in a query string.
  • Allow to set delay_threshold_by_time in milliseconds.
  • Avoid session disconnection issue in failover/failback/backend error in some cases.
  • Allow to route queries to a specific backend node for a specific user connection.
  • Support multiple directories specification for pcp_socket_dir.
  • Import PostgreSQL 16's SQL parser.

You can download it from here.

Release notes: English

Pgpool-II 4.4 RC1 released (2022/11/22)

Pgpool-II 4.4 RC1 is now released.

Note that this is not a stable version but just for developers.

V4.4 contains new features and enhancements, including:

  • Add new dynamic spare process management feature. This feature allows selecting between static and dynamic process management modes.
  • Allow to specify replication delay by time in streaming replication mode. For this purpose new parameter delay_threshold_by_time is introduced.
  • As PostgreSQL already does, Pgpool-II now supports unix_socket_directories, unix_socket_group and unix_socket_permissions for more flexible and precise control of UNIX domain sockets.
  • Allow to use comma separated multiple listen addresses in listen_addresses and pcp_listen_addresses. They control which interfaces accept connection attempts, which can help prevent repeated malicious connection requests on insecure network interfaces.
  • Allow to customize the command used by trusted_servers for checking upstream connection. For this purpose new parameter trusted_server_command is introduced.
  • Import PostgreSQL 15's SQL parser.
  • Speed up query cache by reducing lock contention. This allows concurrent running clients to fetch cache contents much more quicker.

You can download it from here.

Release notes: English

Pgpool-II 4.4 beta1 released (2022/11/14)

Pgpool-II 4.4 beta1 is now released.

Note that this is not a stable version but just for developers.

V4.4 contains new features and enhancements, including:

  • Add new dynamic spare process management feature. This feature allows selecting between static and dynamic process management modes.
  • Allow to specify replication delay by time in streaming replication mode. For this purpose new parameter delay_threshold_by_time is introduced.
  • As PostgreSQL already does, Pgpool-II now supports unix_socket_directories, unix_socket_group and unix_socket_permissions for more flexible and precise control of UNIX domain sockets.
  • Allow to use comma separated multiple listen addresses in listen_addresses and pcp_listen_addresses. They control which interfaces accept connection attempts, which can help prevent repeated malicious connection requests on insecure network interfaces.
  • Allow to customize the command used by trusted_servers for checking upstream connection. For this purpose new parameter trusted_server_command is introduced.
  • Import PostgreSQL 15's SQL parser.
  • Speed up query cache by reducing lock contention. This allows concurrent running clients to fetch cache contents much more quicker.

You can download it from here.

Release notes: English

Pgpool-II 4.3 RC1 released (2021/11/25)

Pgpool-II 4.3 RC1 is now released. Please take a look at 4.3 RC1

Note that this is not a stable version but just for developers.

V4.3 contains new features and enhancements, including:

  • A new membership mechanism is introduced to Watchdog to allow to keep quorum/VIP when some of watchdog nodes are removed.
  • Allow to choose the least replication delay standby node when selecting the load balance node.
  • Allow to specify the node id to be promoted in pcp_promote_node.
  • Allow to configure to not trigger failover when PostgreSQL is shutdown by admin or killed by pg_terminate_backend.
  • Add new fields to pcp_proc_info, SHOW POOL_PROCESSES and SHOW POOL_POOLS command to display more useful information to admin.
  • Allow pcp_node_info to list all backend nodes information.
  • Add new fields showing actual PostgreSQL status to SHOW POOL NODES command and friends.
  • Add a new parameter which represents the recovery source hostname to recovery_1st_stage_command and recovery_2nd_stage_command.
  • Add support for log time stamp with milliseconds.
  • Import PostgreSQL 14's SQL parser.
  • Support include directive in pgppol.conf file. You can have separate sub-config file to be included in pgpool.conf.
  • pgpool.conf sample files are unified into single sample file for easier configuration.
  • All configuration parameters in pgpool.conf sample file are commented out to clarify which parameter is needed to be changed.

You can download it from here.

Release notes: English


Pgpool-II 4.3 beta2 released (2021/11/18)

Pgpool-II 4.3 beta2 is now released. Please take a look at 4.3 beta2

Note that this is not a stable version but just for developers.

V4.3 contains new features and enhancements, including:

  • A new membership mechanism is introduced to Watchdog to allow to keep quorum/VIP when some of watchdog nodes are removed.
  • Allow to choose the least replication delay standby node when selecting the load balance node.
  • Allow to specify the node id to be promoted in pcp_promote_node.
  • Allow to configure to not trigger failover when PostgreSQL is shutdown by admin or killed by pg_terminate_backend.
  • Add new fields to pcp_proc_info, SHOW POOL_PROCESSES and SHOW POOL_POOLS command to display more useful information to admin.
  • Allow pcp_node_info to list all backend nodes information.
  • Add new fields showing actual PostgreSQL status to SHOW POOL NODES command and friends.
  • Add a new parameter which represents the recovery source hostname to recovery_1st_stage_command and recovery_2nd_stage_command.
  • Add support for log time stamp with milliseconds.
  • Import PostgreSQL 14's SQL parser.
  • Support include directive in pgppol.conf file. You can have separate sub-config file to be included in pgpool.conf.
  • pgpool.conf sample files are unified into single sample file for easier configuration.
  • All configuration parameters in pgpool.conf sample file are commented out to clarify which parameter is needed to be changed.

You can download it from here.

Release notes: English

Pgpool-II 4.3 beta1 released (2021/11/09)

Pgpool-II 4.3 beta1 is now released.

Note that this is not a stable version but just for developers.

V4.3 contains new features and enhancements, including:

  • A new membership mechanism is introduced to Watchdog to allow to keep quorum/VIP when some of watchdog nodes are removed.
  • Allow to choose the least replication delay standby node when selecting the load balance node.
  • Allow to specify the node id to be promoted in pcp_promote_node.
  • Allow to configure to not trigger failover when PostgreSQL is shutdown by admin or killed by pg_terminate_backend.
  • Add new fields to pcp_proc_info, SHOW POOL_PROCESSES and SHOW POOL_POOLS command to display more useful information to admin.
  • Allow pcp_node_info to list all backend nodes information.
  • Add new fields showing actual PostgreSQL status to SHOW POOL NODES command and friends.
  • Add a new parameter which represents the recovery source hostname to recovery_1st_stage_command and recovery_2nd_stage_command.
  • Add support for log time stamp with milliseconds.
  • Import PostgreSQL 14's SQL parser.
  • Support include directive in pgppol.conf file. You can have separate sub-config file to be included in pgpool.conf.
  • pgpool.conf sample files are unified into single sample file for easier configuration.
  • All configuration parameters in pgpool.conf sample file are commented out to clarify which parameter is needed to be changed.

You can download it from here.

Release notes: English

Pgpool-II 4.2 beta1 released (2020/10/27)

Pgpool-II 4.2 beta1 is now released.

Note that this is not a stable version but just for developers.

V4.2 contains new features and enhancements, including:

  • Some items in the configuration file pgpool.conf are vastly enhanced for easier configuration and administration.
  • Implement logging_collector for easier log management.
  • Implement log_disconnections to collect disconnection logs.
  • Implement pg_enc and pg_md5 to allow to register multiple passwords at once.
  • Allow to show statistics of health check by using SHOW POOL_HEALTH_CHECK_STATS command, and also allow to show statistics of issued SQL by using SHOW POOL_BACKEND_STATS command.
  • New PCP command pcp_reload_config is added.
  • Now it is possible to omit write_function_list and read_only_function_list by looking at system catalog information.
  • Add new clustering mode snapshot_isolation_mode which guarantees not only data modifications to multiple PostgreSQL but read consistency.
  • Support LDAP authentication between clients and Pgpool-II.
  • Add ssl_crl_file and ssl_passphrase_command to SSL configuration.
  • Import PostgreSQL 13's SQL parser.

You can download it from here.

Release notes: English

Pgpool-II 4.2 alpha1 released (2020/10/06)

Pgpool-II 4.2 alpha1 is now released.

Note that this is not a stable version but just for developers.

V4.2 contains new features and enhancements, including:

  • Some items in the configuration file pgpool.conf are vastly enhanced for easier configuration and administration.
  • Implement logging_collector for easier log management.
  • Implement log_disconnections to collect disconnection logs.
  • Implement pg_enc and pg_md5 to allow to register multiple passwords at once.
  • Allow to show statistics of health check by using SHOW POOL_HEALTH_CHECK_STATS command, and also allow to show statistics of issued SQL by using SHOW POOL_BACKEND_STATS command.
  • New PCP command pcp_reload_config is added.
  • Now it is possible to omit write_function_list and read_only_function_list by looking at system catalog information.
  • Add new clustering mode snapshot_isolation_mode which guarantees not only data modifications to multiple PostgreSQL but read consistency.
  • Support LDAP authentication between clients and Pgpool-II.
  • Add ssl_crl_file and ssl_passphrase_command to SSL configuration.
  • Import PostgreSQL 13's SQL parser.

You can download it from here.

Release notes: English

Pgpool-II 4.1 RC1 released (2019/10/16)

Pgpool-II 4.1 RC1 is now released.

This is not intended to be used in production but is close to the release version. So users are encouraged to test it out.

Major enhancements in Pgpool-II 4.1 include:

  • Statement level load balancing.
  • Auto failback.
  • Enhance performance in number of areas.
    • Shared relation cache allows to reuse relation cache among sessions to reduce internal queries against PostgreSQL system catalogs.
    • Have separate SQL parser for DML statements to eliminate unnecessary parsing effort.
    • Load balancing control for specific queries.
  • Reduce Internal Queries against System Catalogs.
  • Import PostgreSQL 12 SQL parser.
  • etc.

You can download it from here.

Release notes: English

Pgpool-II 4.1 beta1 released (2019/09/06)

Pgpool-II 4.1 beta1 is now released.

This is not a stable version but just for developers.

Major enhancements in Pgpool-II 4.1 include:

  • Statement level load balancing.
  • Auto failback.
  • Enhance performance in number of areas.
    • Shared relation cache allows to reuse relation cache among sessions to reduce internal queries against PostgreSQL system catalogs.
    • Have separate SQL parser for DML statements to eliminate unnecessary parsing effort.
    • Load balancing control for specific queries.
  • Reduce Internal Queries against System Catalogs.
  • Import PostgreSQL 12 SQL parser.
  • etc.

You can download it from here.

Release notes: English

Old

See this page.

Where can I get commercial support for Pgpool-II?

Some commercial packages include Pgpool-II support. Consulting and annual support can be purchased from SRA OSS LLC (https://www.sraoss.co.jp/index_en.php).