From: Oliver Neukum <oliver@neukum.org>
To: Lennart Sorensen <lsorense@csclub.uwaterloo.ca>
Subject: Re: gigabit ethernet power consumption
Date: Wed, 10 Oct 2007 08:35:05 +0200
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Cc: "Kok, Auke" <auke-jan.h.kok@intel.com>, Pavel Machek <pavel@ucw.cz>,
       Arjan van de Ven <arjan@infradead.org>,
       kernel list <linux-kernel@vger.kernel.org>
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Am Dienstag 09 Oktober 2007 schrieb Lennart Sorensen:

> Now if you were trying to transfer a lot of data to the laptop, would it
> be more power efficient to do it at gigabit speeds so you can finish
> sooner and shut down the machine entirely, or to slow to 100mbit and
> take longer to do it, and hence spend more time powering the cpu and
> ram?

There's an amount of data which would be the cutoff point.

But I don't think you can by default make machines slower. So as soon as
the link is saturated you have to switch to the higher speed. To avoid a
ping-pong effect I'd use a timer for bringing the link speed down again.

	Regards
		Oliver


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