Message-ID: <4C2402C3.6080209@2ndquadrant.com>
Date: Thu, 24 Jun 2010 21:13:39 -0400
From: Greg Smith <greg@2ndquadrant.com>
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To: Craig James <craig_james@emolecules.com>
CC: pgsql-performance@postgresql.org
Subject: Re: Occasional giant spikes in CPU load
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	<4BBCFB12.1010306@emolecules.com>	
	<y2r72dbd3151004071556j22244233l8fa1db295b7f9cd3@mail.gmail.com>	
	<r2q603c8f071004071747n3e56d12bo11c49885b8c2eb2e@mail.gmail.com>	
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Craig James wrote:
> Now the question has narrowed down to this: what could trigger EVERY 
> postgres backend to do something at the same time?  See the attached 
> output from "top -b", which shows what is happening during one of the 
> CPU spikes.

By the way:  you probably want "top -b -c", which will actually show you 
what each client is doing via inspecting what it's set its command line to.

-- 
Greg Smith  2ndQuadrant US  Baltimore, MD
PostgreSQL Training, Services and Support
greg@2ndQuadrant.com   www.2ndQuadrant.us