Horton

Re: Vacuum ERRORs out considering freezing dead tuples from before OldestXmin

Melanie Plageman <melanieplageman@gmail.com>

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From: Melanie Plageman <melanieplageman@gmail.com>
To: Peter Geoghegan <pg@bowt.ie>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Heikki Linnakangas <hlinnaka@iki.fi>, Pg Hackers <pgsql-hackers@postgresql.org>, Andres Freund <andres@anarazel.de>, Noah Misch <noah@leadboat.com>
Date: 2024-07-22T13:32:12Z
Lists: pgsql-hackers

Commits

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  1. Test that vacuum removes tuples older than OldestXmin

  2. Lower minimum maintenance_work_mem to 64kB

  3. Add accidentally omitted test to meson build file

  4. Use DELETE instead of UPDATE to speed up vacuum test

  5. Revert "Test that vacuum removes tuples older than OldestXmin"

  6. Ensure vacuum removes all visibly dead tuples older than OldestXmin

On Sun, Jul 21, 2024 at 4:29 PM Peter Geoghegan <pg@bowt.ie> wrote:
>
> On Sun, Jul 21, 2024 at 12:51 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > I do not think the answer to this is to nag the respective animal
> > owners to raise PG_TEST_TIMEOUT_DEFAULT.  IMV this test is simply
> > not worth the cycles it takes, at least not for these machines.
>
> Can't we just move it to PG_TEST_EXTRA? Alongside the existing
> "xid_wraparound" test?
>
> We didn't even have basic coverage of multi-pass VACUUMs before now.
> This new test added that coverage. I think that it will pull its
> weight.

Andres has suggested in the past that we allow maintenance_work_mem be
set to a lower value or introduce some kind of development GUC so that
we can more easily test multiple pass index vacuuming. Do you think
this would be worth it?

- Melanie