Benjamin Krajmalnik wrote: > > -----Original Message----- > > From: Bruce Momjian [mailto:bruce@xxxxxxxxxx] > > Sent: Monday, June 28, 2010 3:45 PM > > To: Benjamin Krajmalnik > > Cc: Rajesh Kumar Mallah; Kevin Grittner; pgsql- > > performance@xxxxxxxxxxxxxx > > Subject: Re: cpu bound postgresql setup. > > > > Benjamin Krajmalnik wrote: > > > Rajesh, > > > > > > I had a similar situation a few weeks ago whereby performance all of > > a > > > sudden decreased. > > > The one tunable which resolved the problem in my case was increasing > > the > > > number of checkpoint segments. > > > After increasing them, everything went back to its normal state. > > > > Did you get a db server log message suggesting in increasing that > > setting? I hope so. > Unfortunately not. The behavior I had was ebbs and flows. On FreeBSD, > I was seeing a lot of kernel wait states in top. So every few minutes, > responsiveness of the db was pretty bad. 8.4.4/amd64 on FreeBSD 7.2 Bummer. What is supposed to happen is if you are checkpointing too frequently ( < 30 seconds), you get the suggestion about increasing checkpoint_segments. I have not heard of cases where you are not checkpointing too frequently, and increasing checkpoint_segments helps. -- Bruce Momjian <bruce@xxxxxxxxxx> http://momjian.us EnterpriseDB http://enterprisedb.com + None of us is going to be here forever. + -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
