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From: Alan Hodgson <ahodgson@simkin.ca>
Organization: Simkin Network Consulting
To: pgsql-performance@postgresql.org
Subject: Re: High CPU Utilization
Date: Mon, 16 Mar 2009 12:52:22 -0700
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On Monday 16 March 2009, Joe Uhl <joeuhl@gmail.com> wrote:
> Right now (not under peak load) this server is running at 68% CPU
> utilization and its SATA raid 10 is doing about 2MB/s writes and 11MB/
> s reads.  When I run dd I can hit 200+MB/s writes and 230+ MB/s reads,
> so we are barely using the available IO.  Further when I run dd the
> CPU utilization of that process only approaches 20%-30% of one core.

What does vmstat say when it's slow? The output of "vmstat 1 30" would be=20
informative.=20

note: dd is sequential I/O. Normal database usage is random I/O.=20

=2D-=20
Even a sixth-grader can figure out that you can=E2=80=99t borrow money to p=
ay off=20
your debt