Re: Re: PD_ALL_VISIBLE flag was incorrectly set happend during repeatable vacuum

daveg <daveg@sonic.net>

From: daveg <daveg@sonic.net>
To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>, Greg Stark <gsstark@mit.edu>
Date: 2011-03-08T08:49:56Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Fix a violation of WAL coding rules in the recent patch to include an

On Tue, Mar 08, 2011 at 10:37:24AM +0200, Heikki Linnakangas wrote:
> On 08.03.2011 10:00, Heikki Linnakangas wrote:
> >Another idea is to give up on the warning when it appears that
> >oldestxmin has moved backwards, and assume that it's actually fine. We
> >could still warn in other cases where the flag appears to be incorrectly
> >set, like if there is a deleted tuple on the page.
> 
> This is probably a better idea at least in back-branches. It also 
> handles the case of twiddling vacuum_defer_cleanup_age, which tracking 
> two xmins per transactions would not handle.
> 
> Here's a patch. I also changed the warning per Robert's suggestion. 
> Anyone see a hole in this?

It would be helpful to have the dbname and schema in the message in addition
to the relname. I added those to the original diagnostic patch as it was not
clear that the messages were all related to the same page/table/dg.

Also, in your comment you might mention that multiple databases are one way
we could see oldestxmin move backwards.

-dg
 

-- 
David Gould       daveg@sonic.net      510 536 1443    510 282 0869
If simplicity worked, the world would be overrun with insects.