Re: another autovacuum scheduling thread

On Wed, 8 Oct 2025 18:25:20 -0700
Jeremy Schneider <schneider(at)ardentperf(dot)com> wrote:

> On Thu, 9 Oct 2025 14:03:34 +1300
> David Rowley <dgrowleyml(at)gmail(dot)com> wrote:
>
> > I thought if we're to have a priority queue that it would be hard to
> > argue against sorting by how far over the given auto-vacuum
> > threshold that the table is. If you assume that a table that just
> > meets the dead rows required to trigger autovacuum based on the
> > autovacuum_vacuum_scale_factor setting gets a priority of 1.0, but
> > another table that has n_mod_since_analyze twice over the
> > autovacuum_analyze_scale_factor gets priority 2.0. Effectively,
> > prioritise by the percentage over the given threshold the table is.
> > That way users could still tune things when they weren't happy with
> > the priority given to a table by adjusting the corresponding
> > reloption.
>
> If users are tuning this thing then I feel like we've already lost the
> battle :)

I replied too quickly. Re-reading your email, I think your proposing a
different algorithm, taking tuple counts into account. No tunables. Is
there a fully fleshed out version of the proposed alternative algorithm
somewhere? (one of the older threads?) I guess this is why its so hard
to get anything committed in this area...

-J