Re: Flaky vacuum truncate test in reloptions.sql

Masahiko Sawada <sawada.mshk@gmail.com>

From: Masahiko Sawada <sawada.mshk@gmail.com>
To: Arseny Sher <a.sher@postgrespro.ru>
Cc: Michael Paquier <michael@paquier.xyz>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2021-03-31T13:17:09Z
Lists: pgsql-hackers
On Tue, Mar 30, 2021 at 10:22 PM Arseny Sher <a.sher@postgrespro.ru> wrote:
>
> On 3/30/21 10:12 AM, Michael Paquier wrote:
>
>  > Yep, this is the same problem as the one discussed for c2dc1a7, where
>  > a concurrent checkpoint may cause a page to be skipped, breaking the
>  > test.
>
> Indeed, Alexander Lakhin pointed me to that commit after I wrote the
> message.
>
>  > Why not just using DISABLE_PAGE_SKIPPING instead here?
>
> I think this is not enough. DISABLE_PAGE_SKIPPING disables vm consulting
> (sets
> aggressive=true in the routine); however, if the page is locked and
> lazy_check_needs_freeze says there is nothing to freeze on it, we again
> don't
> look at its contents closely.

Right.

Is it better to add FREEZE to the first "VACUUM reloptions_test;" as well?

Regards,

-- 
Masahiko Sawada
EDB:  https://www.enterprisedb.com/



Commits

  1. Improve stability of test with vacuum_truncate in reloptions.sql