On Thu, 2009-05-07 at 20:36 +0200, Dimitri wrote: > I've simply restarted a full test with hashjoin OFF. Until 32 > concurrent users things are going well. Then since 32 users response > time is jumping to 20ms, with 64 users it's higher again, and with 256 > users reaching 700ms, so TPS is dropping from 5.000 to ~200.. > > With hashjoin ON it's not happening, and I'm reaching at least 11.000 > TPS on fully busy 32 cores. Much better to stick to the defaults. Sounds like a problem worth investigating further, but not pro bono. > About scalability issue - there is one on 8.3.7, because on 32 cores > with such kind of load it's using only 50% CPU and not outpassing > 6.000 TPS, while 8.4 uses 90% CPU and reaching 11.000 TPS.. Yeh, small changes make a big difference. Thanks for the info. How does MySQL perform? -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
