Re: Vacuum freeze

On Thu, Dec 4, 2014 at 12:02 PM, Mike Blackwell <mike.blackwell@rrd.com> wrote:
> check_postgres.pl (--action=autovac_freeze) recently complained that we
> needed to run VACUUM FREEZE.  Doing so generated a boatload of WAL files -
> perhaps on the order of the of the database itself.
>
> Is VACUUM FREEZE something that is normally handled by autovac?  If so, how
> would we approach finding what caused it not to happen automatically?  Or if
> it's not, what's the normal approach to scheduling it manually to prevent
> this flood of WAL?

It is (supposed to be) handled by autovacuum: you can tune
autovacuum_freeze_max_age:
http://www.postgresql.org/docs/current/static/runtime-config-autovacuum.html

And there are similar knobs for manual VACUUMs as well.

Josh