Re: pg_stat_bgwriter.buffers_backend is pretty meaningless (and more?)

Hi,

On 2023-03-06 10:09:24 -0500, Melanie Plageman wrote:
> On Mon, Mar 6, 2023 at 1:48 AM Kyotaro Horiguchi
> <horikyota.ntt@gmail.com> wrote:
> >
> > At Mon, 06 Mar 2023 15:24:25 +0900 (JST), Kyotaro Horiguchi <horikyota.ntt@gmail.com> wrote in
> > > In any case, I think we need to avoid such concurrent autovacuum/analyze.
> >
> > If it is correct, I believe the attached fix works.
> 
> Thanks for investigating this!
> 
> Yes, this fix looks correct and makes sense to me.

Wouldn't it be better to just perform the section from the ALTER TABLE till
the DROP TABLE in a transaction? Then there couldn't be any other accesses in
just that section. I'm not convinced it's good to disallow all concurrent
activity in other parts of the test.

Greetings,

Andres Freund