Re: pgsql: Avoid creation of the free space map for small heap relations.

On Mon, Jan 28, 2019 at 10:25 AM Andrew Gierth
<andrew(at)tao11(dot)riddles(dot)org(dot)uk> wrote:
>
> >>>>> "Amit" == Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> writes:
>
> Amit> One possibility is that autovacuum has triggered to perform
> Amit> truncation of some other relation (remove pages at the end) which
> Amit> doesn't allow the FSM test to remove the rows/perform truncation
> Amit> and thus let to the failure. Can there be anything else which can
> Amit> start a transaction when a regression test is running? Still
> Amit> thinking, but inputs are welcome.
>
> I've bumped into issues (cf. commit 64ae420b2) with regression tests of
> this kind caused by concurrent (auto-)ANALYZE (not VACUUM);
>

Yes, so this could be the cause of the problem. I think we need to
change the tests added by the patch such that they don't rely on
vacuum to remove dead-row versions? Do you or anybody else see any
better way to fix this?

--
With Regards,
Amit Kapila.
EnterpriseDB: http://www.enterprisedb.com