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From: John Baldwin <jhb@freebsd.org>
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Date: Wed, 16 Jan 2008 10:09:53 -0500
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Cc: njl@freebsd.org, bruno@freebsd.org,
	Stefan Lambrev <stefan.lambrev@moneybookers.com>,
	Igor Mozolevsky <igor@hybrid-lab.co.uk>,
	Dag-Erling =?iso-8859-1?q?Sm=F8rgrav?= <des@des.no>,
	Maxim Sobolev <sobomax@digifonica.com>
Subject: Re: powerd adaptive mode latching
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On Saturday 12 January 2008 04:27:46 pm Maxim Sobolev wrote:
> I wonder if somebody did measurement of power consumption with powerd 
> and without it on typical tasks. There is very interesting idea in the 
> last issue of ACM Queue that it might be much more beneficial to run CPU 
> at the full speed and then switch it to low-power mode as soon as 
> possible in the idle loop than to run longer at reduced speed for a 
> longer period of time.

I haven't done hard tests, but even with C3 enabled on my laptop I find that
anecdotally I get longer battey life with powerd enabled.

-- 
John Baldwin