From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761502AbYBYWXc (ORCPT ); Mon, 25 Feb 2008 17:23:32 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757447AbYBYWXV (ORCPT ); Mon, 25 Feb 2008 17:23:21 -0500 Received: from rtr.ca ([76.10.145.34]:1457 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758834AbYBYWXU (ORCPT ); Mon, 25 Feb 2008 17:23:20 -0500 Message-ID: <47C34081.5090205@rtr.ca> Date: Mon, 25 Feb 2008 17:26:09 -0500 From: Mark Lord Organization: Real-Time Remedies Inc. User-Agent: Thunderbird 2.0.0.9 (X11/20071031) MIME-Version: 1.0 To: Pavel Machek Cc: kernel list , Linux-pm mailing list , stern@rowland.harvard.edu, linux-ide@vger.kernel.org Subject: Re: [ugly patch] Save .15W-.5W by AHCI powersaving References: <20080225134558.GA1611@elf.ucw.cz> In-Reply-To: <20080225134558.GA1611@elf.ucw.cz> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Pavel Machek wrote: > Hi! > > This is a patch (very ugly, assumes you have just one disk) to bring > powersaving to AHCI. You need Alan's SCSI autosuspend (attached) patch > as a base. > > It saves .5W compared to config with disk spinning, and even .15W > compared to hdparm -y... on my thinkpad x60 anyway. .. There was a discussion of this here today. It makes good use of AHCI-specific features. Has it been tested with a Port-Multiplier yet? This is cool enough that we really ought to do a hardware-independent version, so that all SATA interfaces could benefit. Especially ata_piix, but others too. Cheers