Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965104AbWHWTnY (ORCPT ); Wed, 23 Aug 2006 15:43:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965152AbWHWTnX (ORCPT ); Wed, 23 Aug 2006 15:43:23 -0400 Received: from mexforward.lss.emc.com ([128.222.32.20]:15735 "EHLO mexforward.lss.emc.com") by vger.kernel.org with ESMTP id S965104AbWHWTnX (ORCPT ); Wed, 23 Aug 2006 15:43:23 -0400 Message-ID: <44ECAFB4.8060206@emc.com> Date: Wed, 23 Aug 2006 15:42:44 -0400 From: Ric Wheeler Reply-To: ric@emc.com User-Agent: Mozilla Thunderbird 1.0.7 (X11/20050923) X-Accept-Language: en-us, en MIME-Version: 1.0 To: "Mario 'BitKoenig' Holbe" CC: linux-kernel@vger.kernel.org Subject: Re: [patch 4/5] fail-injection capability for disk IO References: <20060823113243.210352005@localhost.localdomain> <20060823113317.722640313@localhost.localdomain> <20060823121028.GE5893@suse.de> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-PMX-Version: 4.7.1.128075, Antispam-Engine: 2.4.0.264935, Antispam-Data: 2006.8.1.75432 X-PerlMx-Spam: Gauge=, SPAM=2%, Reasons='EMC_FROM_0+ -2, __CP_MEDIA_BODY 0, __CT 0, __CTE 0, __CT_TEXT_PLAIN 0, __HAS_MSGID 0, __MIME_TEXT_ONLY 0, __MIME_VERSION 0, __SANE_MSGID 0, __USER_AGENT 0' Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1304 Lines: 37 Mario 'BitKoenig' Holbe wrote: > Jens Axboe wrote: > >>On Wed, Aug 23 2006, Andi Kleen wrote: >> >>>I think I would prefer a stackable driver instead of this hook. > > > I second this, preferrably a device-mapper target similar to dm-error. > > >>But that makes it more tricky to setup a test, since you have to change >>from using /dev/sda (for example) to /dev/stacked-driver. > > > Do you really think somebody would run such tests on otherwise normally > used devices? > We certainly run this kind of tests on a routine basis - before we ship a kernel to our installed field, we need to verify that it will handle disk IO errors correctly. In our case, the tests are run on a farm of machines that get pxe'ed to a specific image, tested (usually by sticking in a disk known to be bad enough to cause reliable errors ;-)) and then we watch to see that the errors do not cause hangs, etc. Having a requirement to change our standard image (sda -> stacked-driver) would not be impossible, but would be less convenient... ric - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/