> So I think we need to sort by age(relfrozenxid) in tables that are over > the anti-wraparound limit. Given your code that doesn't seem to be that > hard?
I might also suggest that we think about changing the defaults for wraparound vacuum behavior. Partcularly, the fact that vacuum_freeze_min_age is 50% of autovacuum_freeze_max_age by default is optimal for absolutely nobody, and forces re-wraparound vacuuming of wraparound tables which were just recently wraparound-vacuumed. We should lower vacuum_freeze_min_age to something sane, like 1000000. (background: http://www.databasesoup.com/2012/10/freezing-your-tuples-off-part-2.html) Also, while I don't know if Alvaro's optimization is a net gain or not (It might be), I do agree that backpatching it is not worth considering. -- Josh Berkus PostgreSQL Experts Inc. http://pgexperts.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
