e2eb95f1a3
GetSnapshotData() set TransactionXmin = MyProc->xmin, but when SnapshotResetXmin() advanced MyProc->xmin, it did not advance TransactionXmin correspondingly. That meant that TransactionXmin could be older than MyProc->xmin, and XIDs between than TransactionXmin and the real MyProc->xmin could be vacuumed away. One known consequence is in pg_subtrans lookups: we might try to look up the status of an XID that was already truncated away. Back-patch to all supported versions. Reviewed-by: Andres Freund Discussion: https://www.postgresql.org/message-id/d27a046d-a1e4-47d1-a95c-fbabe41debb4@iki.fi
Percona Server for PostgreSQL
Percona Server for PostgreSQL is a free, enhanced, fully compatible, open source, drop-in replacement for the PostgreSQL Database Management System with enterprise-grade features. It requires no changes to PostgreSQL applications or code.
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 Percona Server for PostgreSQL can be found at https://docs.percona.com/postgresql/17/. In particular, information about building PostgreSQL from the source code can be found at https://docs.percona.com/postgresql/17/installing.html.
Submit a bug report or a feature request
If you find a bug in Percona Server for PostgreSQL, you can submit a report to the project's Jira issue tracker
As a general rule of thumb, please try to create a bug report that is:
Reproducible - include the steps on how to reproduce the issue
Specific - include as much detail as possible, such as which version, which environment, etc.
Unique - do not duplicate existing tickets
Scoped to a single issue - only one issue per report