Message-ID: 
 <12692871.1127953531542.JavaMail.root@elwamui-polski.atl.sa.earthlink.net>
Date: Wed, 28 Sep 2005 20:25:31 -0400 (EDT)
From: Ron Peacetree <rjpeace@earthlink.net>
Reply-To: Ron Peacetree <rjpeace@earthlink.net>
To: Kevin Grittner <Kevin.Grittner@wicourts.gov>,
	pgsql-hackers@postgresql.org, pgsql-performance@postgresql.org
Subject: Re: [PERFORM] A Better External Sort?
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If I've done this correctly, there should not be anywhere near
the number of context switches we currently see while sorting.

Each unscheduled context switch represents something unexpected
occuring or things not being where they are needed when they are
needed.  Reducing such circumstances to the absolute minimum 
was one of the design goals.

Reducing the total amount of IO to the absolute minimum should
help as well. 

Ron


-----Original Message-----
From: Kevin Grittner <Kevin.Grittner@wicourts.gov>
Sent: Sep 27, 2005 11:21 AM
Subject: Re: [HACKERS] [PERFORM] A Better External Sort?

I can't help wondering how a couple thousand context switches per
second would affect the attempt to load disk info into the L1 and
L2 caches.  That's pretty much the low end of what I see when the
server is under any significant load.