On 15.10.2013 01:26, Tony Kay wrote: > Hi Calvin, > > Yes, I have sar data on all systems going back for years. > > Since others are going to probably want to be assured I am really > "reading the data" right: > > - This is 92% user CPU time, 5% sys, and 1% soft > - On some of the problems, I _do_ see a short spike of pgswpout's > (memory pressure), but again, not enough to end up using much system time > - The database disks are idle (all data being used is in RAM)..and are > SSDs....average service times are barely measurable in ms.
OK. Can you share the data? Maybe we'll notice something suspicious. > If I had to guess, I'd say it was spinlock misbehavior....I cannot > understand why ekse a transaction blocking other things would drive > the CPUs so hard into the ground with user time. Have you tried running perf, to verify the time is actually spent on spinlocks? Tomas -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
