E.4. Postgres Pro Standard 10.20.1

Release Date: 2022-02-21

E.4.1. Overview

This release is based on PostgreSQL 10.20 and Postgres Pro Standard 10.19.1. All changes inherited from PostgreSQL 10.20 are listed in PostgreSQL 10.20 Release Notes. Other major changes and enhancements are as follows:

  • Fixed the out-of-memory (OOM) killer settings in system startup files. Previously the OOM score adjustment value was set for all Postgres Pro processes rather than for postmaster only, so when Postgres Pro exhausted all RAM, the OOM killer could start killing irrelevant processes, such as sshd.

  • Ended support for outdated operating systems Debian 8, Astra Linux Smolensk 1.5 and MSVSphere 6.3.

  • Upgraded pg_probackup to version 2.5.5, which provides the following new features and bugfixes as compared to the previous included version 2.5.3:

    • Added the --checkunique option to the checkdb command to work together with --amcheck and verify unique constraints during logical verification of indexes when the amcheck extension is installed in the database and its version supports the verification of unique constraints. Check the amcheck documentation for whether this verification is supported.

    • Fixed an issue that could occur when the source database was not on the timeline 1 and the destination database did not fall behind: probackup sanity checks on catchup timeline history failed with the error Destination is not in source timeline history.

    • Fixed the behavior of catchup in DELTA and PTRACK modes. The fixed issue could occur when pg_probackup operated remotely via SSH and --destination-pgdata was the same as --source-pgdata, caused corruption of the source instance (at least the global/pg_control, global/pg_filenode.map and base/*/pg_filenode.map files got deleted) and resulted in the error Could not open file "/pgwal/test/global/pg_control" for reading: No such file or directory.

E.4.2. Migration to Version 10.20.1

If you are upgrading from a Postgres Pro Standard version based on the same PostgreSQL major release, it is enough to install the new version into your current installation directory.

While functions numeric_eq, numeric_ne, numeric_gt, numeric_ge, numeric_lt, and numeric_le are actually leakproof, they were not marked as such in Postgres Pro Standard 10.11.1 or lower, which could lead to incorrect query optimization. In particular, it negatively affected query execution if row-level security policy was in use. Version 10.12.1 repairs this issue for new installations by correcting the initial catalog data, but existing installations will still have incorrect markings unless you update pg_proc entries for these functions. You can run pg_upgrade to upgrade your server instance to a version containing the corrected initial data, or manually correct these entries in each database of the installation using the ALTER FUNCTION command. For example:

ALTER FUNCTION pg_catalog.numeric_eq LEAKPROOF

Starting from Postgres Pro Standard 10.11.1, the ICU library upgrade does not interfere with the server start. Before connecting to a database using ICU as the default collation, Postgres Pro compares this collation version to the one provided by the ICU library and displays a warning if the collation versions do not match; you may need to rebuild the objects that depend on the default collation if you think the collation change may affect the sort order of your data. To suppress these warnings, you can use the ALTER COLLATION "default" REFRESH VERSION command, as explained in ALTER COLLATION.

Since pg_probackup delivery model changed in Postgres Pro Standard 10.7.1, when upgrading from a lower version on ALT Linux and Debian-based systems, run apt dist-upgrade (or apt-get dist-upgrade) to ensure that all new dependencies are handled correctly. On Windows, you have to run a separate pg_probackup installer to complete the upgrade.

When upgrading from version 10.3.2 or lower, you must call the REINDEX command for indexes that used mchar or mvarchar types. Besides, if you have been using pg_repack on Debian-based systems, you have to reinstall its package manually when upgrading to this version since its package got renamed to pg-repack-std-10.

To migrate from PostgreSQL or a Postgres Pro Standard release based on a previous PostgreSQL major version, see the migration instructions for version 10. If you are opting for a dump/restore, make sure to use the --add-collprovider option to correctly choose the provider for the default collation of the migrated database.