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To: Dan Harris <fbsd@drivefaster.net>
cc: PostgreSQL Performance <pgsql-performance@postgresql.org>
Subject: Re: Simple query showing 270 hours of CPU time 
In-reply-to: <46A0EE6B.6040707@drivefaster.net> 
References: <46A0D836.5090806@drivefaster.net>
 <10727.1184949725@sss.pgh.pa.us>
	<46A0EE6B.6040707@drivefaster.net>
Comments: In-reply-to Dan Harris <fbsd@drivefaster.net>
	message dated "Fri, 20 Jul 2007 11:18:35 -0600"
Date: Fri, 20 Jul 2007 14:12:26 -0400
Message-ID: <11835.1184955146@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Dan Harris <fbsd@drivefaster.net> writes:
> Since you mentioned the number of semops is distressingly high, does this 
> indicate a tuning problem?

More like an old-version problem.  We've done a lot of work on
concurrent performance since 8.0.x, and most likely you are hitting
one of the bottlenecks that have been solved since then.

			regards, tom lane