Re: vacuum question

Kevin Kempter <kevink@consistentstate.com> wrote:
> INFO: "action_rollup_notifier": found 0 removable, 34391214
> nonremovable row versions in 152175 pages
> DETAIL: 22424476 dead row versions cannot be removed yet.
> There were 0 unused item pointers.
> 2 pages contain useful free space.
> 0 pages are entirely empty.

> Anyone have any suggestions per why these rows cannot be removed
> yet?

The only time I've seen numbers like that is when there was a
long-running transaction which was preventing VACUUM from cleaning
anything up.  (In our case it was a programmer using an unapproved
tool against a production server; the tool issued a BEGIN TRANSACTION
and just sat there.)

Look at the pg_stat_activity table.  If you have any values in
xact_start more than a few seconds old, you've identified your
culprit.  I'm betting it will be "idle in transaction".

-Kevin