From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [linux-pm] power draw depending on PHY speed Date: Fri, 28 Aug 2009 21:03:59 +0200 Message-ID: <200908282103.59159.rjw@sisk.pl> References: <76FA3B279DD9DA48896E2B40494495720368E449@USA7061MS02.na.xerox.net> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: linux-pm@lists.linux-foundation.org, martyleisner@yahoo.com, NetDEV list To: "Leisner, Martin" Return-path: Received: from ogre.sisk.pl ([217.79.144.158]:44619 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752000AbZH1TDI (ORCPT ); Fri, 28 Aug 2009 15:03:08 -0400 In-Reply-To: <76FA3B279DD9DA48896E2B40494495720368E449@USA7061MS02.na.xerox.net> Sender: netdev-owner@vger.kernel.org List-ID: On Friday 28 August 2009, Leisner, Martin wrote: > While doing some current probe measurements (i.e. to measure the effects > of NAP and frequency scaling with a freescale processor) I noticed some > very > significant differents if we ran on 100Mbit of 1000Mbit ethernet. > > The hardware guys like at their data sheets and agreed. > > Does anyone "drop ethernet speed" to save power? > (when a system is idle, is isn't necessary to run 1G ethernet). I don't know, really. This is a netdev question IMO (CC added). > When a system has WOL capability, what speed does it run at when the > system is sleeping? That's a very good question. I bet that depends on the NIC in question, at least I'm not sure if any spec regulates it. Thanks, Rafael