Hi Bruce, On Tue, Apr 14, 2026 at 6:19 PM Bruce Momjian <[email protected]> wrote: > > I have completed the first draft of the PG 19 release notes: > > https://www.postgresql.org/docs/devel/release-19.html > > The feature count is 212. The recent average is 200: > > https://momjian.us/main/writings/pgsql/missing.pdf#page=3 > > I will create a wiki page to explain my methods used to create this > because, someday, someone else will need to do this. > > I am traveling April 19 to May 7, so I might not be able to make quick > adjustments based on feedback. Another committer can handle them, or > you can wait for me to get to it.
I've pushed a fix (8628df8891a) for how parallel vacuum computes the cost-based vacuum delay. As I mentioned in the commit message, while the fix corrects the delay computation, it could make VACUUM with the PARALLEL option and cost-based delay enabled slower after upgrading to v19. I think it's worth mentioning this in the release notes so that users can re-tune the cost-based delay parameters. I've attached the patch to add the item to the "Migration to Version 19" section. Please review it. Regards, -- Masahiko Sawada Amazon Web Services: https://aws.amazon.com
diff --git a/doc/src/sgml/release-19.sgml b/doc/src/sgml/release-19.sgml index 253fa07179a..7939d44aa36 100644 --- a/doc/src/sgml/release-19.sgml +++ b/doc/src/sgml/release-19.sgml @@ -303,6 +303,22 @@ large analytical queries to manually enable <acronym>JIT</acronym>. </para> </listitem> +<!-- +Author: Masahiko Sawada <[email protected]> +2026-11-02 [8628df889] Make parallel vacuum processes share the cost limit. +--> + +<listitem> +<para> +Make the leader and workers of a <link linkend="parallel-vacuum">parallel vacuum</link> share the cost-based vacuum delay limit (Bharath Rupireddy) +<ulink url="&commit_baseurl;8628df889">§</ulink> +</para> + +<para> +Previously each process slept based only on the cost it incurred itself, so a parallel vacuum could consume several times the budget set by <link linkend="guc-vacuum-cost-limit"><varname>vacuum_cost_limit</varname></link>. As a result, <link linkend="sql-vacuum"><command>VACUUM</command></link> with parallel workers and cost-based delay enabled can run slower than in previous releases. +</para> +</listitem> + <!-- Author: Amit Kapila <[email protected]> 2025-11-18 [3edaf29fa] Rename two columns in pg_stat_subscription_stats.
