On 2014-10-09 18:16:46 -0300, Alvaro Herrera wrote: > Andres Freund wrote: > > On 2014-10-09 18:03:00 -0300, Alvaro Herrera wrote: > > > Bruce Momjian wrote: > > > > > > > I agree this is a serious problem. We have discussed various options, > > > > but have not decided on anything. The TODO list has: > > > > > > > > https://wiki.postgresql.org/wiki/Todo > > > > > > > > Improve setting of visibility map bits for read-only and > > > > insert-only > > > > workloads > > > > > > > > > > > > http://www.postgresql.org/message-id/20130906001437.ga29...@momjian.us > > > > > > I hate to repeat myself, but I think autovacuum could be modified to run > > > actions other than vacuum and analyze. In this specific case we could > > > be running a table scan that checks only pages that don't have the > > > all-visible bit set, and see if it can be set. > > > > Isn't that *precisely* what a plain vacuum run does? > > Well, it also scans for dead tuples, removes them, and needs to go > through indexes to remove their references.
IIRC it doesn't do most of that if that there's no need. And if it's a insert only table without rollbacks. I *do* think there's some optimizations we could make in general. > I'm thinking in something > very lightweight. Otherwise, why don't we just reduce the > vacuum_scale_factor default to something very small, so that vacuum is > triggered more often? The problem here is that that doesn't trigger for inserts. Just for updates/deletes or rollbacks. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, 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
