Re: Problem with pg_upgrade?

On Wed, 2011-03-30 at 16:46 -0400, Robert Haas wrote:
> I don't really
> understand why this is an issue in the first place, though.  Surely we
> must be setting the XID counter on the new cluster to match the one on
> the old cluster, and migrating the relfrozenxid and datfrozenxid
> settings, so why does it matter if someone runs vacuum freeze?

Because autovacuum may run before those things are properly set, as
Bruce said in the original email:

"I am concerned that somehow autovaccum is running
in frozen mode before I have restored the frozen xids for the table or
database."

I think some kind of hidden GUC might be the best option. I tend to
agree that a third option to the "autovacuum" setting would be
confusing.

Regards,Jeff Davis