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Date: Thu, 8 May 2003 12:57:59 -0700
From: Sean Chittenden <sean@chittenden.org>
To: The Hermit Hacker <scrappy@postgresql.org>
Cc: lista@profit-ti.com.br, pgsql-hackers@postgresql.org
Subject: Re: Hyper-Threading
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> I've heard conflicting reports about HyperThreading in general
> ... by default, FreeBSD doesn't enable it (it originally did), as
> ppl were reporting performance degradation ... I'm using it on our
> servers, and haven't noticed any problems ...

Twiddle with the sysctl machdep.cpu_idle_hlt, that seemed to make a
big difference in terms of power consumption, heat, and effectiveness
of HTT.  As the previous poster suggested, HTT promises lots, but
delivers little.  Search the archives on FreeBSD.org for a set of
rather large threads regarding this topic.  -sc

-- 
Sean Chittenden