From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755162AbWKMPs7 (ORCPT ); Mon, 13 Nov 2006 10:48:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755163AbWKMPs6 (ORCPT ); Mon, 13 Nov 2006 10:48:58 -0500 Received: from srv5.dvmed.net ([207.36.208.214]:35722 "EHLO mail.dvmed.net") by vger.kernel.org with ESMTP id S1755162AbWKMPs6 (ORCPT ); Mon, 13 Nov 2006 10:48:58 -0500 Message-ID: <455893E5.4010001@garzik.org> Date: Mon, 13 Nov 2006 10:48:53 -0500 From: Jeff Garzik User-Agent: Thunderbird 1.5.0.8 (X11/20061107) MIME-Version: 1.0 To: Andi Kleen CC: Pavel Machek , John Fremlin , kernel list , htejun@gmail.com, jim.kardach@intel.com Subject: Re: AHCI power saving (was Re: Ten hours on X60s) References: <87k639u55l.fsf-genuine-vii@john.fremlin.org> <20061113142219.GA2703@elf.ucw.cz> <45589008.1080001@garzik.org> <200611131637.56737.ak@suse.de> In-Reply-To: <200611131637.56737.ak@suse.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: -4.3 (----) X-Spam-Report: SpamAssassin version 3.1.7 on srv5.dvmed.net summary: Content analysis details: (-4.3 points, 5.0 required) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Andi Kleen wrote: >> Therein lies a key problem. Turning on all of AHCI's aggressive power >> management features DOES save a lot of power. But at the same time, it >> shortens the life of your hard drive, particularly hard drives that are >> really PATA, but have a PATA<->SATA bridge glued on the drive to enable >> connection to SATA controllers. > > How does it shorten its life? Parks your hard drive heads many thousands of times more often than it does without the aggressive PM features. Jeff