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

On 2024-07-22 12:00:51 -0400, Peter Geoghegan wrote:
> On Mon, Jul 22, 2024 at 11:49 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > >> 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?
> >
> > > No, I don't.
> >
> > I don't see why that's not a good idea.
> 
> I don't think that it's worth going to that trouble. Testing multiple
> passes isn't hard -- not in any real practical sense.

It's hard by now (i.e. 17+) because you need substantial amounts of rows to be
able to trigger it which makes it a hard fight to introduce. And the cost of
setting the GUC limit lower is essentially zero.

What's the point of having such a high lower limit?

Greetings,

Andres Freund