Re: Introduce some randomness to autovacuum

On Thu, 1 May 2025 at 03:29, Nathan Bossart <nathandbossart(at)gmail(dot)com> wrote:
> That being said, I am -1 for this proposal. Autovacuum parameters and
> scheduling are already quite complicated, and making it nondeterministic
> would add an additional layer of complexity (and may introduce its own
> problems). But more importantly, IMHO it masks the problems instead of
> solving them more directly, and it could mask future problems, too. It'd
> probably behoove us to think about the known problems more deeply and to
> craft more targeted solutions.

-1 from me too.

It sounds like the aim is to fix the problem with autovacuum vacuuming
the same table over and over and being unable to remove enough dead
tuples due to something holding back the oldest xmin horizon. Why
can't we just fix that by remembering the value that
VacuumCutoffs.OldestXmin and only coming back to that table once
that's moved forward some amount?

David