Re: Intermittent test plan change in "privileges" test on BF animal prion - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Intermittent test plan change in "privileges" test on BF animal prion
Date
Msg-id 2155068.1591674901@sss.pgh.pa.us
Whole thread Raw
In response to Re: Intermittent test plan change in "privileges" test on BF animal prion  (David Rowley <dgrowleyml@gmail.com>)
Responses Re: Intermittent test plan change in "privileges" test on BF animal prion  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
David Rowley <dgrowleyml@gmail.com> writes:
> On Tue, 9 Jun 2020 at 15:41, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Hmm ... that's a plausible theory, perhaps.  I forget: does autovac
>> recheck, after acquiring the requisite table lock, whether the table
>> still needs to be processed?

> It does, but I wondered if there was a window after the manual vacuum
> resets n_ins_since_vacuum and between when autovacuum looks at it.

Oh, there surely is, because of the lag in the stats collection mechanism.
I'm trying to reproduce this now, but it's sounding pretty plausible.

BTW, it looks like I managed to trim the reference off my prior message,
but I meant [1] to refer to
https://www.postgresql.org/message-id/666679.1591138428%40sss.pgh.pa.us

            regards, tom lane



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