Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752739AbZIRHHd (ORCPT ); Fri, 18 Sep 2009 03:07:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750950AbZIRHHc (ORCPT ); Fri, 18 Sep 2009 03:07:32 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:43216 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750836AbZIRHHc (ORCPT ); Fri, 18 Sep 2009 03:07:32 -0400 Date: Fri, 18 Sep 2009 00:05:42 -0700 From: Andrew Morton To: Hugh Dickins Cc: "Zhang, Yanmin" , Peter Zijlstra , LKML , Ingo Molnar , Arjan van de Ven , Andi Kleen , "lee.schermerhorn@hp.com" , stable@kernel.org Subject: Re: aim7 scalability issue on 4 socket machine Message-Id: <20090918000542.268934e1.akpm@linux-foundation.org> In-Reply-To: References: <1253179879.2606.37.camel@ymzhang> <1253180411.8497.1.camel@twins> <1253239339.2606.40.camel@ymzhang> <20090917195909.3a00ef83.akpm@linux-foundation.org> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2018 Lines: 50 On Fri, 18 Sep 2009 07:53:58 +0100 (BST) Hugh Dickins wrote: > On Thu, 17 Sep 2009, Andrew Morton wrote: > > On Fri, 18 Sep 2009 10:02:19 +0800 "Zhang, Yanmin" wrote: > > > > > > > > So, Yanmin, please retest with http://lkml.org/lkml/2009/9/13/25 > > > > and let us know if that works as well for you - thanks. > > > I tested Lee's patch and it does fix the issue. > > Thanks for checking and reporting back, Yanmin. > > > > > Do we think we should cook up something for -stable? > > Gosh, I laughed at Lee (sorry!) for suggesting it for -stable: > is stable really for getting a better number out of a benchmark? > > I'd have thought the next release is the right place for that; but > I've no problem if you guys and the stable guys agree it's appropriate. > > > > > Either this is a regression or the workload is particularly obscure. > > I've not cross-checked descriptions, but assume Lee was actually > testing on exactly the same kind of upcoming Nehalem as Yanmin, and > that machine happens to have characteristics which show up badly here. > > > > > aim7 is sufficiently non-obscure to make me wonder what's happened here? > > Not a regression, just the onward march of new hardware, I think. > Could easily be other such things in other places with other tests. > Well, it comes down to the question "what is -stable for". If you take it as "bugfixed version of the 2.6.x kernel" then no, speedups aren't appropriate. If you consider -stable to be "something distros, etc will use" then yes, perhaps we serve those consumers better by including fairly major efficiency improvements. I suspect most consumers of -stable would prefer the latter approach, as long as we don't go nuts. -- 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/