From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756635AbYJ3WD7 (ORCPT ); Thu, 30 Oct 2008 18:03:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753101AbYJ3WDu (ORCPT ); Thu, 30 Oct 2008 18:03:50 -0400 Received: from ipmail05.adl2.internode.on.net ([203.16.214.145]:24736 "EHLO ipmail05.adl2.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752631AbYJ3WDu (ORCPT ); Thu, 30 Oct 2008 18:03:50 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApoEAGXJCUl5LIvD/2dsb2JhbADMS4NR X-IronPort-AV: E=Sophos;i="4.33,518,1220193000"; d="scan'208";a="244383539" Date: Fri, 31 Oct 2008 09:03:44 +1100 From: Dave Chinner To: Christoph Lameter Cc: David Rientjes , Andrew Morton , Nick Piggin , Peter Zijlstra , Paul Menage , Derek Fults , linux-kernel@vger.kernel.org Subject: Re: [patch 0/7] cpuset writeback throttling Message-ID: <20081030220344.GL4985@disturbed> Mail-Followup-To: Christoph Lameter , David Rientjes , Andrew Morton , Nick Piggin , Peter Zijlstra , Paul Menage , Derek Fults , linux-kernel@vger.kernel.org References: <20081030210826.GR17077@disturbed> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 30, 2008 at 04:33:34PM -0500, Christoph Lameter wrote: > On Fri, 31 Oct 2008, Dave Chinner wrote: > >> What sort of validation/regression testing has this been through? > > There were several tests run more than a year ago by me on large SGI > machines. Then there was Solomita who did various tests and posts of the > patchset over the last year. Yes, I know about those tests at SGI - they were to demonstrate the feature worked (i.e. proof-of-concept demonstration), not regression test the change. This is a fairly major change in behaviour to the writeback path on NUMA systems and so has the potential to introduce subtle new issues. Hence I'm asking about the level of testing and exposure it has had. It doesn't really sound like it has had much coverage to me.... I'm concerned right now because Nick and others (including myself) have recently found lots of nasty data integrity problems in the writeback path that we are currently trying to test fixes for. It's not a good time to introduce new behaviours as that will definitely perturb any regression testing we are running.... Cheers, Dave. -- Dave Chinner david@fromorbit.com