> From: Josh Berkus <j...@agliodbs.com> >To: Scott Marlowe <scott.marl...@gmail.com> >Cc: pgsql-performance@postgresql.org >Sent: Thursday, 21 February 2013, 3:14 >Subject: Re: [PERFORM] High CPU usage / load average after upgrading to Ubuntu >12.04 > > >> Sounds to me like your IO system is stalling on fsyncs or something >> like that. On machines with plenty of IO cranking up completion >> target usuall smooths things out. > >It certainly seems like it does. However, I can't demonstrate the issue >using any simpler tool than pgbench ... even running four test_fsyncs in >parallel didn't show any issues, nor do standard FS testing tools. >
I've missed a load of this thread and just scanned through what I can see, so apologies if I'm repeating anything. If the suspicion is the IO system and you've tuned everything you can think of; is there anything interesting in meminfo/iostat/vmstat before/during the stalls? If so can you cause anything similar via bonnie++ with the "-b" option? -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
