Horton

Re: recovering from "found xmin ... from before relfrozenxid ..."

Ashutosh Sharma <ashu.coek88@gmail.com>

View thread View on postgr.es
From: Ashutosh Sharma <ashu.coek88@gmail.com>
To: "Andrey M. Borodin" <x4mmm@yandex-team.ru>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Andres Freund <andres@anarazel.de>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, Tom Lane <tgl@sss.pgh.pa.us>, Stephen Frost <sfrost@snowman.net>, Robert Haas <robertmhaas@gmail.com>
Date: 2020-07-31T12:32:24Z
Lists: pgsql-hackers 
On Wed, Jul 29, 2020 at 9:58 AM Ashutosh Sharma <ashu.coek88@gmail.com>
wrote:

>
> > I think we should let VACUUM do that.
>> Sometimes VACUUM will not get to these pages, because they are marked All
>> Frozen.
>> An possibly some tuples will get stale on this page again
>>
>
> Hmm, okay, will have a look into this. Thanks.
>

I had a look over this and found that one can use the DISABLE_PAGE_SKIPPING
option with VACUUM to disable all its page-skipping behavior.

-- 
With Regards,
Ashutosh Sharma
EnterpriseDB:http://www.enterprisedb.com

Commits

  1. Fix wrong data table horizon computation during backend startup.

  2. Centralize horizon determination for temp tables, fixing bug due to skew.

  3. pg_surgery: Try to stabilize regression tests.

  4. New contrib module, pg_surgery, with heap surgery functions.

  5. Set cutoff xmin more aggressively when vacuuming a temporary table.

  6. snapshot scalability: Don't compute global horizons while building snapshots.

  7. Introduce vacuum errcontext to display additional information.