From mboxrd@z Thu Jan 1 00:00:00 1970 From: Auke Kok Subject: Re: Runtime power management for network interfaces Date: Mon, 31 Jul 2006 09:19:18 -0700 Message-ID: <44CE2D86.3040800@intel.com> References: <44C644B6.20208@intel.com> <20060730200631.836bdd23.rdunlap@xenotime.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: stern@rowland.harvard.edu, netdev@vger.kernel.org, david-b@pacbell.net Return-path: Received: from mga01.intel.com ([192.55.52.88]:64905 "EHLO fmsmga101-1.fm.intel.com") by vger.kernel.org with ESMTP id S1030217AbWGaQUp (ORCPT ); Mon, 31 Jul 2006 12:20:45 -0400 To: "Randy.Dunlap" In-Reply-To: <20060730200631.836bdd23.rdunlap@xenotime.net> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Randy.Dunlap wrote: > On Tue, 25 Jul 2006 09:20:06 -0700 Auke Kok wrote: > >> Alan Stern wrote: >>> During a Power Management session at the Ottawa Linux Symposium, it was >>> generally agreed that network interface drivers ought to automatically >>> suspend their devices (if possible) whenever: >>> >>> (1) The interface is ifconfig'ed down, or >>> >>> (2) No link is available. >>> >>> Presumably (1) should be easy enough to implement. (2) might or might not >>> be feasible, depending on how much WOL support is available. (It might >>> not be feasible at all for wireless networking.) Still, there can be no >>> question that it would be a Good Thing for laptops to power-down their >>> ethernet controllers when the network cable is unplugged. >>> >>> Has any progress been made in this direction? If not, a natural approach >>> would be to start with a reference implementation in one driver which >>> could then be copied to other drivers. >> >> Intel's newer e1000's (ich7 onboard e1000 and newer versions for instance) >> already support this feature partially - the MAC stays on but the PHY can be >> powered off when no link is present. >> >> In order to enable this feature you will need to turn it on explicitly at load >> time: >> >> modprobe e1000 SmartPowerDownEnable=1 > > Please add that to Documentation/networking/e1000.txt. I'm long overdue with documentation updates ATM, I'll see if I can fix that :) Cheers, Auke