Re: Postmaster only takes 4-5% CPU

On Thu, 29 May 2003, Ruben wrote:

> Hi all:
>
> When I run a (big) query from pgsql, postmaster used to take almost 100%
> of CPU. Now, with aparent no reason, Postmaster only takes 4-5% CPU and
> the same query takes really longer to finish.
>
> I have tried renicing -20 postmaster but it still only takes a small
> percentage of CPU, while 90% is idle.
>
> This is a "top" screen while running the query:
>
> 2:27pm up 5 min, 2 users, load average: 0,80, 0,26, 0,08
> 74 processes: 72 sleeping, 2 running, 0 zombie, 0 stopped
> CPU states: 3,1% user, 2,1% system, 0,0% nice, 94,6% idle
> Mem: 1031012K av, 246040K used, 784972K free, 0K shrd, 11496K
> buff
> Swap: 2040244K av, 0K used, 2040244K free 196916K
> cached
>
> PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME COMMAND
> 1165 postgres 0 -20 3476 3476 2912 D < 4,5 0,3 0:02 postmaster
> 268 root 15 0 0 0 0 SW 0,1 0,0 0:00 kjournald
>
> Any idea of how can I get postmaster to eat as much CPU as possible?

Looks like you're waiting on I/O. What's your disk subsystem
configuration?