From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262223AbTJIOLy (ORCPT ); Thu, 9 Oct 2003 10:11:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262224AbTJIOLx (ORCPT ); Thu, 9 Oct 2003 10:11:53 -0400 Received: from ns.virtualhost.dk ([195.184.98.160]:33773 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S262223AbTJIOLv (ORCPT ); Thu, 9 Oct 2003 10:11:51 -0400 Date: Thu, 9 Oct 2003 16:11:43 +0200 From: Jens Axboe To: Marcelo Tosatti Cc: Jeff Garzik , Linux Kernel Mailing List Subject: Re: [PATCH] laptop mode Message-ID: <20031009141143.GF1232@suse.de> References: <3F856A7E.2010607@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 09 2003, Marcelo Tosatti wrote: > > > On Thu, 9 Oct 2003, Jeff Garzik wrote: > > > Linux Kernel Mailing List wrote: > > > ChangeSet 1.1150.1.52, 2003/10/08 10:49:45-03:00, axboe@suse.de > > > > > > [PATCH] laptop mode > > > > > > Hi Marcelo, > > > > > > Lots of people have been using this patch with great success, and it's > > > been in the SuSE kernel for some months now too. It is also in the -benh > > > ppc tree > > > > > > Basically, it introduces a write back mode of dirty and journal data > > > that is more suitable for laptops. At the block layer end, it schedules > > > write out of dirty data after the disk has been idle for 5 seconds. > > > > > > Laptop mode can be switched on and off with /proc/sys/vm/laptop_mode. > > > There is also a block_dump sysctl, which if enabled will dump who > > > dirties and writes out data. This is very helpful in pinning down who is > > > causing unnecessary writes to the disk. > > > > Red Hat just dropped this patch since it was suspected of data > > corruption ;-( > > Uh, oh... Jens? See my previous mail. I don't see any problems with it, and I've certainly not heard of (or experienced myself) problems with the patch. I'm waiting for Jeff to expand on his mail, surely he/RH must know more about this issue. -- Jens Axboe