Horton

Re: Should vacuum process config file reload more often

Melanie Plageman <melanieplageman@gmail.com>

View thread View on postgr.es
From: Melanie Plageman <melanieplageman@gmail.com>
To: Daniel Gustafsson <daniel@yesql.se>
Cc: Robert Haas <robertmhaas@gmail.com>, Andres Freund <andres@anarazel.de>, Tom Lane <tgl@sss.pgh.pa.us>, Masahiko Sawada <sawada.mshk@gmail.com>, Kyotaro Horiguchi <horikyota.ntt@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>, Amit Kapila <amit.kapila16@gmail.com>
Date: 2023-04-06T22:12:22Z
Lists: pgsql-hackers

Attachments

On Thu, Apr 6, 2023 at 5:45 PM Daniel Gustafsson <daniel@yesql.se> wrote:
>
> > On 6 Apr 2023, at 23:06, Melanie Plageman <melanieplageman@gmail.com> wrote:
>
> > Autovacuum workers, at the end of VacuumUpdateCosts(), check if cost
> > limit or cost delay have been changed. If they have, they assert that
> > they don't already hold the AutovacuumLock, take it in shared mode, and
> > do the logging.
>
> Another idea would be to copy the values to local temp variables while holding
> the lock, and release the lock before calling elog() to avoid holding the lock
> over potential IO.

Good idea. I've done this in attached v19.
Also I looked through the docs and everything still looks correct for
balancing algo.

- Melanie

Commits

  1. Fix assertion failure in heap_vacuum_rel

  2. Fix vacuum_cost_delay check for balance calculation.

  3. Fix autovacuum cost debug logging

  4. Refresh cost-based delay params more frequently in autovacuum

  5. Separate vacuum cost variables from GUCs

  6. Make vacuum failsafe_active globally visible

  7. Don't balance vacuum cost delay when per-table settings are in effect