>>> Scott Marlowe <scott.marl...@gmail.com> wrote: > On Fri, Feb 13, 2009 at 7:02 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: >> Scott Marlowe <scott.marl...@gmail.com> writes: >>> On Fri, Feb 13, 2009 at 5:02 PM, Michael Monnerie >>> <michael.monne...@is.it-management.at> wrote: >>>> vacuum_cost_delay = 0 >>>> That was the trick for me. It was set to 250(ms), where it took 5 >>>> hours for a vacuum to run. Now it takes 5-15 minutes. >> >>> Wow!!! 250 ms is HUGE in the scheme of vacuum cost delay. even >>> 10ms is usually plenty to slow down vacuum enough to keep it out >>> of your way and double to quadruple your vacuum times. >> >> I wonder whether we ought to tighten the allowed range of >> vacuum_cost_delay. The upper limit is 1000ms at the moment; >> but that's clearly much higher than is useful, and it seems >> to encourage people to pick silly values ... > > I agree. I can't imagine using a number over 50 or so.
I don't know what other people have found useful, but when I experimented with this in our environment, it seemed like I should just treat vacuum_cost_delay as a boolean, where 0 meant off and 10 meant on, and tune it by adjusting vacuum_cost_limit. The granularity of vacuum_cost_delay is course and surprising unpredictable. -Kevin -- Sent via pgsql-admin mailing list (pgsql-admin@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
