Excerpts from Russell Smith's message of mié jun 02 06:38:35 -0400 2010: > Don't you not get a positive enough effect by adjusting the table's > autovacuum_min_freeze_age and autovacuum_max_freeze_age. If you set > those numbers small, it appears to me that you would get very quickly to > a state where the vacuum would example only the most recent part of the > table rather than the whole thing.
The problem is that vacuum doesn't know that a certain part of the table is already frozen. It needs to scan it completely anyways. If we had a "frozen" map, we could mark pages that are completely frozen and thus do not need any vacuuming; but we don't (I don't recall the reasons for this. Maybe it's just that no one has gotten around to it, or maybe there's something else). -- Álvaro Herrera <alvhe...@commandprompt.com> The PostgreSQL Company - Command Prompt, Inc. PostgreSQL Replication, Consulting, Custom Development, 24x7 support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers