mirror of
https://github.com/postgres/postgres.git
synced 2025-05-27 00:04:24 -04:00
e28bb88519
This reverts commit d9d076222f5b "VACUUM: ignore indexing operations with CONCURRENTLY". These changes caused indexes created with the CONCURRENTLY option to miss heap tuples that were HOT-updated and HOT-pruned during the index creation. Before these changes, HOT pruning would have been prevented by the Xmin of the transaction creating the index, but because this change was precisely to allow the Xmin to move forward ignoring that backend, now other backends scanning the table can prune them. This is not a problem for VACUUM (which requires a lock that conflicts with a CREATE INDEX CONCURRENTLY operation), but HOT-prune can definitely occur. In other words, Xmin advancement was sped up, but at the cost of corrupting the resulting index. Regrettably, this means that the new feature in PG14 that RIC/CIC on very large tables no longer force VACUUM to retain very old tuples goes away. We might try to implement it again in a later release, but for now the risk of indexes missing tuples is too high and there's no easy fix. Backpatch to 14, where this change appeared. Reported-by: Peter Slavov <pet.slavov@gmail.com> Diagnosys-by: Andrey Borodin <x4mmm@yandex-team.ru> Diagnosys-by: Michael Paquier <michael@paquier.xyz> Diagnosys-by: Andres Freund <andres@anarazel.de> Discussion: https://postgr.es/m/17485-396609c6925b982d%40postgresql.org
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. PostgreSQL has many language interfaces, many of which are listed here: https://www.postgresql.org/download/ See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.