From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261376AbVEIOII (ORCPT ); Mon, 9 May 2005 10:08:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261375AbVEIOHx (ORCPT ); Mon, 9 May 2005 10:07:53 -0400 Received: from stat16.steeleye.com ([209.192.50.48]:13726 "EHLO hancock.sc.steeleye.com") by vger.kernel.org with ESMTP id S261376AbVEIOHh (ORCPT ); Mon, 9 May 2005 10:07:37 -0400 Subject: Re: Suspend/Resume From: James Bottomley To: Pavel Machek Cc: Jens Axboe , Jon Escombe , Linux Kernel , Jeff Garzik In-Reply-To: <20050509101344.GA24478@atrey.karlin.mff.cuni.cz> References: <4267B5B0.8050608@davyandbeth.com> <20050502144703.GA1882@suse.de> <20050503141017.GD6115@suse.de> <1115524401.5942.13.camel@mulgrave> <20050509101344.GA24478@atrey.karlin.mff.cuni.cz> Content-Type: text/plain Date: Mon, 09 May 2005 09:07:21 -0500 Message-Id: <1115647641.5051.1.camel@mulgrave> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-4) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2005-05-09 at 12:13 +0200, Pavel Machek wrote: > In IDE we do that to reliably flush drive caches... If write caching > actually works on SCSI, we should not need that hacks. Define "works". Actual write caching works fine with IDE (it doesn't lose the data). On the other hand, turning the cache off or flushing it can be problematic because not all IDE devices respond to these commands. So, what I think you're saying is that you don't want the internal drives to spin down, but you do want to send a synchronize cache command to those which have a writeback cache enabled? James