From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261802AbUEVTPh (ORCPT ); Sat, 22 May 2004 15:15:37 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261830AbUEVTPh (ORCPT ); Sat, 22 May 2004 15:15:37 -0400 Received: from cantor.suse.de ([195.135.220.2]:38380 "EHLO Cantor.suse.de") by vger.kernel.org with ESMTP id S261802AbUEVTPg (ORCPT ); Sat, 22 May 2004 15:15:36 -0400 Subject: Re: [PATCH] ext3 barrier bits From: Chris Mason To: Andrew Morton Cc: arjanv@redhat.com, axboe@suse.de, linux-kernel@vger.kernel.org In-Reply-To: <20040522013313.6cb15a4b.akpm@osdl.org> References: <20040521093207.GA1952@suse.de> <20040521023807.0de63c7a.akpm@osdl.org> <20040521100234.GK1952@suse.de> <20040521235044.6160cccb.akpm@osdl.org> <20040522073540.GO1952@suse.de> <20040522011139.01a7da10.akpm@osdl.org> <1085214261.2781.1.camel@laptop.fenrus.com> <20040522013313.6cb15a4b.akpm@osdl.org> Content-Type: text/plain Message-Id: <1085253331.9467.4982.camel@watt.suse.com> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Sat, 22 May 2004 15:15:32 -0400 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2004-05-22 at 04:33, Andrew Morton wrote: > Arjan van de Ven wrote: > > > > > > > - Does the kernel tell you if your disk doesn't supoprt barriers? ie: > > > how does the user know if it's working or not? > > > > ... and how do you know your disk isn't lying and ignoring the barriers? > > > > If some benchmark slows down when barriers are enabled then that's a pretty > good indicator. I don't know what benchmark that might be though. synctest -t 20 -n 1 -f dir, should show a performance hit when barriers are on. -chris