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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dennis Brouwer <dennis.brouwer@m4n.nl>
cc: pgsql-admin@postgresql.org
Subject: Re: CPU causes 100% load in user space when ntp client runs and
	postgresql is under heavy load
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Comments: In-reply-to Dennis Brouwer <dennis.brouwer@m4n.nl>
	message dated "Tue, 25 Sep 2012 14:58:31 +0200"
Date: Tue, 25 Sep 2012 11:57:36 -0400
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Dennis Brouwer <dennis.brouwer@m4n.nl> writes:
> I now have excluded ntp as root cause for the CPU cycles being wasted in
> user space.

Good, cause that wasn't making any sense at all.

> I installed perf and monitored two servers (with different postgresql
> versions and hardware specification) which are "hanging" and have some
> output. Since I'm no die-hard at interpreting the output of perf top what
> would be the next step to do?

I'd suggest asking for help in pgsql-performance.  I don't know much
about perf either (still an oprofile guy), but the people who do know
it hang out there.

			regards, tom lane