On 2014-10-20 19:43:38 -0500, Jim Nasby wrote: > On 10/20/14, 7:31 PM, Andres Freund wrote: > >On 2014-10-20 19:18:31 -0500, Jim Nasby wrote: > >>>In the meantime, I think it's worth adding this logging. If in fact this > >>>basically never happens (the current assumption), it doesn't hurt > >>>anything. If it turns out our assumption is wrong, then we'll actually be > >>>able to fin> that out.:) > >It does happen, and not infrequently. Just not enough pages to normally > >cause significant bloat. The most likely place where it happens is very > >small tables that all connections hit with a high frequency. Starting to > >issue high volume log spew for a nonexistant problem isn't helping. > > How'd you determine that? Is there some way to measure this?
You'd seen individual pages with too old dead rows in them. > >If you're super convinced this is urgent then add it as a*single* > >datapoint inside the existing messages. But I think there's loads of > >stuff in vacuum logging that are more important this. > > See my original proposal; at it's most intrusive this would issue one > warning per (auto)vacuum if it was over a certain threshold. Which would vastly increase the log output for setups with small tables and a nonzero log_autovacuum_min_duration. 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
