----- "Stephen Frost" <sfrost@xxxxxxxxxxx> wrote: | From: "Stephen Frost" <sfrost@xxxxxxxxxxx> | To: "Rajesh Kumar. Mallah" <mallah@xxxxxxxxxxxxxx> | Cc: pgsql-performance@xxxxxxxxxxxxxx | Sent: Thursday, May 24, 2012 9:27:37 PM | Subject: Re: High load average in 64-core server , no I/O wait and CPU is idle | | Rajesh, | | * Rajesh Kumar. Mallah (mallah@xxxxxxxxxxxxxx) wrote: | > We are puzzled why the CPU and DISK I/O system are not being | utilized | > fully and would seek lists' wisdom on that. | | What OS is this? What kernel version? Dear Frost , We are running linux with kernel 3.2.X (which has the lseek improvements) | | > just a thought, will it be a good idea to partition the host | hardware | > to 4 equal virtual environments , ie 1 for master (r/w) and 3 | slaves r/o | > and distribute the r/o load on the 3 slaves ? | | Actually, it might help with 9.1, if you're really running into some | scalability issues in our locking area.. You might review this: | | http://rhaas.blogspot.com/2012/04/did-i-say-32-cores-how-about-64.html | | That's a pretty contrived test case, but I suppose it's possible your | case is actually close enough to be getting affected also.. Thanks for the reference , even i thought so (LockManager) , but we are actually also running out db max connections (also) ( which is currently at 600) , when that happens something at the beginning of the application stack also gets dysfunctional and it changes the very input to the system. ( think of negative feedback systems ) It is sort of complicated but i will definitely update list , when i get to the point of putting the blame on DB :-) . Regds Mallah. | | Thanks, | | Stephen -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
