From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [patch 0/3] AHCI Link Power Management Date: Mon, 11 Jun 2007 22:33:25 -0400 Message-ID: <466E05F5.3090501@garzik.org> References: <20070611114600.7fca1c24.kristen.c.accardi@intel.com> <466DFDB5.9030901@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <466DFDB5.9030901@gmail.com> Sender: linux-ide-owner@vger.kernel.org To: Tejun Heo Cc: Kristen Carlson Accardi , james.bottomley@steeleye.com, linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, arjan@linux.intel.com List-Id: linux-scsi@vger.kernel.org Tejun Heo wrote: > Kristen Carlson Accardi wrote: >> Hi, >> This series of patches enables Aggressive Link Power Management for AHCI >> devices, as documented in the AHCI spec. On my laptop (a Lenovo X60), this >> saves me a full watt of power. On other systems, reported power savings >> range from .5-1.5 Watts. It has been tested by the kind folks at #powertop >> with similar results. Please give it a try and let me know what you think. > > I'm not sure about this. We need better PM framework to support > powersaving in other controllers and some ahcis don't save much when > only link power management is used, they need to be turned off A better PM framework would definitely be nice :) > completely && I don't think scsi sysfs is the right place to export this > interface. That's about the only place we have right now. Jeff