Re: [PERFORM] High CPU usage / load average after upgrading to Ubuntu 12.04

2013-02-25 Thread Jeff Frost
On 02/20/13 19:14, Josh Berkus wrote: >> 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 a

Re: [PERFORM] Avoiding Recheck Cond when using Select Distinct

2013-02-25 Thread Jeff Janes
On Mon, Feb 25, 2013 at 10:11 AM, Maciek Sakrejda wrote: > On Sat, Feb 23, 2013 at 3:53 PM, Jeff Janes wrote: > > It would really help to have "explain (analyze, buffers)". Especially if > > you turn on track_io_timing, (although that part probably can't be done > on > > Heroku, as it requires s

Re: [PERFORM] Avoiding Recheck Cond when using Select Distinct

2013-02-25 Thread Maciek Sakrejda
On Sat, Feb 23, 2013 at 3:53 PM, Jeff Janes wrote: > It would really help to have "explain (analyze, buffers)". Especially if > you turn on track_io_timing, (although that part probably can't be done on > Heroku, as it requires superuser access.) Right, that's not supported right now, although g

Re: [PERFORM] Are bitmap index scans slow to start?

2013-02-25 Thread Carlo Stonebanks
Hi Jeff, thanks for the insight. << And then the next question would be, once they are in the cache, why don't they stay there? For that you would have to know what other types of activities are going on that might be driving the data out of the cache. >> To give you an idea of the activ