ac0e33136a
This commit introduces idle_replication_slot_timeout GUC that allows inactive slots to be invalidated at the time of checkpoint. Because checkpoints happen checkpoint_timeout intervals, there can be some lag between when the idle_replication_slot_timeout was exceeded and when the slot invalidation is triggered at the next checkpoint. To avoid such lags, users can force a checkpoint to promptly invalidate inactive slots. Note that the idle timeout invalidation mechanism is not applicable for slots that do not reserve WAL or for slots on the standby server that are synced from the primary server (i.e., standby slots having 'synced' field 'true'). Synced slots are always considered to be inactive because they don't perform logical decoding to produce changes. The slots can become inactive for a long period if a subscriber is down due to a system error or inaccessible because of network issues. If such a situation persists, it might be more practical to recreate the subscriber rather than attempt to recover the node and wait for it to catch up which could be time-consuming. Then, external tools could create replication slots (e.g., for migrations or upgrades) that may fail to remove them if an error occurs, leaving behind unused slots that take up space and resources. Manually cleaning them up can be tedious and error-prone, and without intervention, these lingering slots can cause unnecessary WAL retention and system bloat. As the duration of idle_replication_slot_timeout is in minutes, any test using that would be time-consuming. We are planning to commit a follow up patch for tests by using the injection point framework. Author: Nisha Moond <nisha.moond412@gmail.com> Author: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com> Reviewed-by: Peter Smith <smithpb2250@gmail.com> Reviewed-by: Hayato Kuroda <kuroda.hayato@fujitsu.com> Reviewed-by: Vignesh C <vignesh21@gmail.com> Reviewed-by: Amit Kapila <amit.kapila16@gmail.com> Reviewed-by: Hou Zhijie <houzj.fnst@fujitsu.com> Reviewed-by: Bertrand Drouvot <bertranddrouvot.pg@gmail.com> Discussion: https://postgr.es/m/CALj2ACW4aUe-_uFQOjdWCEN-xXoLGhmvRFnL8SNw_TZ5nJe+aw@mail.gmail.com Discussion: https://postgr.es/m/OS0PR01MB5716C131A7D80DAE8CB9E88794FC2@OS0PR01MB5716.jpnprd01.prod.outlook.com
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.