Re: priority on a process

On Fri, 16 May 2003, Johnson, Shaunn wrote:

> Running PostgreSQL 7.2.1 on RedHat Linux 7.2
>
> Q1: how can I move the priority of the job up so that
> it can take advantage of the CPU / memory alloted?
>
> Q2: why will some jobs hog system resouces and others,
> like this one, won't do much of anything?

More than likely you are I/O bound.  i.e. Postgresql is waiting on the
disk subsystem to return data.  See if you can raise shared buffers a bit,
the default 64 is awfully small, 500 to 1000 is a nice place to start.
They're measured in 8k blocks, by the way, so 1024 of them are only 8 megs
cache.  that little change alone speeds up postgresql quite a bit.

Also, if your machine has memory to spare, look at increasing the effect
cache size.  If this is set too low, postgresql will favor seq scans,
which are I/O intensive, but not usually CPU intensive.

If postgresql is running fast enough, then you can ignore all my advice,
if it's running a little slow, then this might help.