5bbc596391
This spec fails ~3% of my Valgrind runs, and the spec has failed on Valgrind buildfarm member skink at a similar rate. Two problems contributed to that: - A competing buffer pin triggered VACUUM's lazy_scan_noprune() path, causing "tuples missed: 1 dead from 1 pages not removed due to cleanup lock contention". FREEZE fixes that. - The spec ran lazy VACUUM immediately after VACUUM FULL. The spec implicitly assumed lazy VACUUM prunes the one tuple that VACUUM FULL made dead. First wait for old snapshots, making that assumption reliable. This also adds two forms of defense in depth: - Wait for snapshots using shared catalog pruning rules (VISHORIZON_SHARED). This avoids the removable cutoff moving backward when an XID-bearing autoanalyze process runs in another database. That may never happen in this test, but it's cheap insurance. - Use lazy VACUUM option DISABLE_PAGE_SKIPPING. Commit c2dc1a79767a0f947e1145f82eb65dfe4360d25f did this for a related requirement in other tests, but I suspect FREEZE is necessary and sufficient in all these tests. Back-patch to v17, where the test first appeared. Reported-by: Andres Freund <andres@anarazel.de> Discussion: https://postgr.es/m/sv3taq4e6ea4qckimien3nxp3sz4b6cw6sfcy4nhwl52zpur4g@h6i6tohxmizu Backpatch-through: 17
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/.