Dne 4.4.2011 16:32, Kevin Grittner napsal(a): > Nothing there makes a write glut on checkpoint less likely to be the > cause. Without a BBU write-back cache it is actually *more* likely, > and having enough RAM to hold the whole database makes it *more* > likely. If you haven't placed your pg_xlog directory on a separate > file system, it is also more likely. > > Turning on logging of checkpoint activity and checking whether that > correlates with your problem times is strongly indicated. > > -Kevin Checkpoints would be my first guess too, but the whole database is just 500MB. Lars, how did you get this number? Did you measure the amount of disk space occupied or somehow else? BTW how much memory is there (total RAM and dedicated to shared buffers)? How many checkpoint segments are there? Have you monitored the overall behavior of the system (what processes are running etc.) when the problems occur? I don't have much experience with Windows but tools from sysinternals are reasonable. And yet another idea - have you tried to use the stats collected by PostgreSQL? I mean the pg_stat_ tables, especially pg_stat_bgwriter and maybe pg_stat_all_tables. Those numbers are cummulative, so do two snapshot when the problems are happening and subtract them to get an idea of what's going on. regards Tomas -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
