Re: pgsql: autovacuum: handle analyze for partitioned tables

Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> On 2021-Apr-08, Tom Lane wrote:
>> Yeah.  I hit this on another machine that isn't using EXEC_BACKEND,
>> and I concur it looks more like a race condition.  I think the problem
>> is that autovacuum is calling find_all_inheritors() on a relation it
>> has no lock on, contrary to that function's API spec.

> Hmm.  Autovacuum tries hard to avoid grabbing locks on relations until
> really needed (at vacuum/analyze time), which is why all these tests
> only use data that can be found in the pg_class rows and pgstat entries.

Yeah, I was worried about that.

> So I tend to think that my initial instinct was the better direction: we
> should not be doing any find_all_inheritors() here at all, but instead
> rely on pg_class.reltuples to be set for the partitioned table.

+1

            regards, tom lane