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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Craig James <cjames@emolecules.com>
cc: pgsql-performance@postgresql.org
Subject: Re: Hyperthreading (was: Two identical systems,
	radically different performance)
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Comments: In-reply-to Craig James <cjames@emolecules.com>
	message dated "Tue, 09 Oct 2012 13:12:55 -0700"
Date: Tue, 09 Oct 2012 16:53:12 -0400
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Craig James <cjames@emolecules.com> writes:
> I've confirmed that hyperthreading causes a huge drop in performance on a
> 2x4-core Intel Xeon E5620 2.40GHz system.  The bottom line is:

Interesting.

> I'll be upgrading to 8.4.14 and making more changes to postgres.conf based
> on feedback.  The server is available for a day or so for more tests if
> anyone has suggestions.

It would be nice to see similar tests done with 9.2.  8.4 is kind of old
news as far as server performance is concerned.

			regards, tom lane