On Wed, 11 May 2022 at 03:44, Bruce Momjian <br...@momjian.us> wrote: > > I have completed the first draft of the PG 15 release notes and you can > see the results here: > > https://momjian.us/pgsql_docs/release-15.html
Thanks for doing that tedious work. I think the sort improvements done in v15 are worth a mention under General Performance. The commits for this were 91e9e89dc, 40af10b57 and 697492434. I've been running a few benchmarks between v14 and v15 over the past few days and a fairly average case speedup is about 25%. but there are cases where I've seen up to 400%. I think the increase is to an extent that we maybe should have considered making tweaks in cost_tuplesort(). I saw some plans that ran in about 60% of the time by disabling Hash Agg and allowing Sort / Group Agg to do the work. David
