Jim Nasby wrote: > While warning a client that just did a Slony-based version upgrade to make > sure to freeze the new database, it occurred to me that it should be safe to > freeze without the cleanup lock. This is interesting because it would allow > a scan_all vacuum to do it's job without blocking on the cleanup lock. > > Does anyone have a feel for whether scan_all vacuums blocking on the cleanup > lock is an actual problem?
Yeah, I remember we discussed this and some other possible improvements related to freezing. I think other ideas proposed were that (1) during an emergency (uncancellable) autovacuum run, we process only the tables that are past the age limit, and (2) we remove the cost-based sleep so that it finishes as quickly as possible. (Yours is (3) only freeze and not do any actual pruning -- did I get that right?) -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
