From owner-freebsd-current@FreeBSD.ORG  Fri Jan 27 16:56:48 2006
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To: Mike Jakubik <mikej@rogers.com>
In-reply-to: Your message of "Fri, 27 Jan 2006 04:03:14 EST."
	<43D9E1D2.6060207@rogers.com> 
Date: Fri, 27 Jan 2006 08:56:44 -0800
From: "Kevin Oberman" <oberman@es.net>
Message-Id: <20060127165644.4F9F245083@ptavv.es.net>
Cc: John-Mark Gurney <gurney_j@resnet.uoregon.edu>, current@freebsd.org,
	Brian Candler <B.Candler@pobox.com>,
	Peter Jeremy <PeterJeremy@optushome.com.au>, arch@freebsd.org,
	Poul-Henning Kamp <phk@phk.freebsd.dk>
Subject: Re: [TEST/REVIEW] CPU accounting patches 
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> Date: Fri, 27 Jan 2006 04:03:14 -0500
> From: Mike Jakubik <mikej@rogers.com>
> Sender: owner-freebsd-current@freebsd.org
> 
> Brian Candler wrote:
> > I guess this is OK, *if* you trust the power management system to do its job
> > properly. Unfortunately I have very bad experiences of such things. In many
> > cases I've ended up turning off power management completely and locking
> > everything at max clock speed. Mind you, if I do that, anything you do with
> > scaling factors isn't going to affect me, so actually I don't really care.
> > I'll shut up now :-)
> >   
> 
> Let's not forget, FreeBSD is really a server OS. Who in their right mind 
> uses power saving features on a server? It sounds nice in theory, but 
> doesn't work as well.

Playing devil's advocate a bit, don't forget that thermal management will
throttle performance even if it is set to maximum (as it should be on a
compute server). This should never happen, but fans and air coolers do
fail.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman@es.net			Phone: +1 510 486-8634