Re: Unexpected VACUUM FULL failure

Tom Lane wrote:
> This is a bit disturbing:
>
> *** ./expected/vacuum.out Sat Jul 20 00:58:14 2002
> --- ./results/vacuum.out Wed Aug 8 20:16:45 2007
> ***************
> *** 50,55 ****
> --- 50,56 ----
>
> DELETE FROM vactst WHERE i != 0;
> VACUUM FULL vactst;
> + ERROR: HEAP_MOVED_OFF was expected
> DELETE FROM vactst;
> SELECT * FROM vactst;
> i
>
> ======================================================================
>
> This is today's CVS HEAD, plus some startup/shutdown logic changes in
> postmaster.c that hardly seem like they could be related.
>
> I couldn't reproduce it in a few tries. A reasonable guess is that
> it's triggered by autovacuum deciding to vacuum the table sometime
> before the VACUUM FULL starts. Anyone want to try to reproduce it?

Hum, aren't vacuums supposed to be blocked by each other? Maybe this is
about a toast table not being locked enough against concurrent vacuuming
of the main table.

I'm currently away on vacation, which is why I've missed all the stuff
going on here. Sorry for not letting people know.

--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.