From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Galbraith Subject: Re: [Bug #11308] tbench regression on each kernel release from 2.6.22 -> 2.6.28 Date: Wed, 17 Sep 2008 15:57:38 +0200 Message-ID: <1221659858.8818.13.camel@marge.simson.net> References: <1221306287.5213.111.camel@marge.simson.net> <48CD1D25.9080301@linux-foundation.org> <1221421907.4597.24.camel@marge.simson.net> <1221475440.4784.39.camel@marge.simson.net> <1221568105.5020.17.camel@marge.simson.net> <1221626391.5043.13.camel@marge.simson.net> <1221627676.5125.3.camel@marge.simson.net> <20080917104044.GC18764@elte.hu> <1221651701.5102.17.camel@marge.simson.net> <20080917124943.GA7738@elte.hu> <1221657111.5511.14.camel@marge.simson.net> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="iso-8859-1" To: Ilpo =?ISO-8859-1?Q?J=E4rvinen?= Cc: Ingo Molnar , Christoph Lameter , "Rafael J. Wysocki" , LKML , kernel-testers-u79uwXL29TY76Z2rM5mHXA@public.gmane.org On Wed, 2008-09-17 at 16:36 +0300, Ilpo J=C3=A4rvinen wrote: > On Wed, 17 Sep 2008, Mike Galbraith wrote: >=20 > > On Wed, 2008-09-17 at 14:49 +0200, Ingo Molnar wrote: > >=20 > > > git log --pretty=3Dformat:"%h: %s" 2069f45..847106f | grep -viE \ > > > 'block|alsa|pcmcia|sound|Merge|iosched|blk|DAC960|scsi|s390|parid= e|pktcdvd|filter|cdrom|drm' > > >=20 > > > gives us: > > >=20 > > > 7daf705: Start using the new '%pS' infrastructure to print symbo= ls > > > 6f0f0fd: security: remove register_security hook > > > 93cbace: security: remove dummy module fix > > > 5915eb5: security: remove dummy module > > > b478a9f: security: remove unused sb_get_mnt_opts hook > > > 32502b8: splice: fix generic_file_splice_read() race with page i= nvalidation > > > 8b3d356: ramfs: enable splice write > > > a144ff0: xen: Avoid allocations causing swap activity on the res= ume path > > >=20 > > > which really only leaves that security commit your bisection fing= ered.=20 > > > Which _slightly_ raises its likelyhood of being implicated. Struc= ture=20 > > > size changes can move two formerly far-apart netperf-relevant sym= bols on=20 > > > the same cacheline, which can start cache ping-pong-ing badly. > >=20 > > I sure hope it's something like ping-pong, it's driving me NUTS. >=20 > How about dividing the problem to smaller blocks then by restoring=20 > parts of the change... Well, what I've done is check out the "bad" tree, reverted every darn commit between there and the "good" tree, and then reverted the reverts so I have a nice merge-free line and don't have to remember to think backward. (probably sounds silly to git-foo masters) I'll try bisecting that in the a.m. and see what happens. -Mike From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754167AbYIQN5x (ORCPT ); Wed, 17 Sep 2008 09:57:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752463AbYIQN5o (ORCPT ); Wed, 17 Sep 2008 09:57:44 -0400 Received: from mail.gmx.net ([213.165.64.20]:33594 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751875AbYIQN5n (ORCPT ); Wed, 17 Sep 2008 09:57:43 -0400 X-Authenticated: #14349625 X-Provags-ID: V01U2FsdGVkX1/B5zUuw+nB64frENwUKPAujBanr2X8XsR8MZCFIi swKxNK9QwizNqG Subject: Re: [Bug #11308] tbench regression on each kernel release from 2.6.22 -> 2.6.28 From: Mike Galbraith To: Ilpo =?ISO-8859-1?Q?J=E4rvinen?= Cc: Ingo Molnar , Christoph Lameter , "Rafael J. Wysocki" , LKML , kernel-testers@vger.kernel.org In-Reply-To: References: <1221306287.5213.111.camel@marge.simson.net> <48CD1D25.9080301@linux-foundation.org> <1221421907.4597.24.camel@marge.simson.net> <1221475440.4784.39.camel@marge.simson.net> <1221568105.5020.17.camel@marge.simson.net> <1221626391.5043.13.camel@marge.simson.net> <1221627676.5125.3.camel@marge.simson.net> <20080917104044.GC18764@elte.hu> <1221651701.5102.17.camel@marge.simson.net> <20080917124943.GA7738@elte.hu> <1221657111.5511.14.camel@marge.simson.net> Content-Type: text/plain; charset=utf-8 Date: Wed, 17 Sep 2008 15:57:38 +0200 Message-Id: <1221659858.8818.13.camel@marge.simson.net> Mime-Version: 1.0 X-Mailer: Evolution 2.22.1.1 Content-Transfer-Encoding: 8bit X-Y-GMX-Trusted: 0 X-FuHaFi: 0.57 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2008-09-17 at 16:36 +0300, Ilpo Järvinen wrote: > On Wed, 17 Sep 2008, Mike Galbraith wrote: > > > On Wed, 2008-09-17 at 14:49 +0200, Ingo Molnar wrote: > > > > > git log --pretty=format:"%h: %s" 2069f45..847106f | grep -viE \ > > > 'block|alsa|pcmcia|sound|Merge|iosched|blk|DAC960|scsi|s390|paride|pktcdvd|filter|cdrom|drm' > > > > > > gives us: > > > > > > 7daf705: Start using the new '%pS' infrastructure to print symbols > > > 6f0f0fd: security: remove register_security hook > > > 93cbace: security: remove dummy module fix > > > 5915eb5: security: remove dummy module > > > b478a9f: security: remove unused sb_get_mnt_opts hook > > > 32502b8: splice: fix generic_file_splice_read() race with page invalidation > > > 8b3d356: ramfs: enable splice write > > > a144ff0: xen: Avoid allocations causing swap activity on the resume path > > > > > > which really only leaves that security commit your bisection fingered. > > > Which _slightly_ raises its likelyhood of being implicated. Structure > > > size changes can move two formerly far-apart netperf-relevant symbols on > > > the same cacheline, which can start cache ping-pong-ing badly. > > > > I sure hope it's something like ping-pong, it's driving me NUTS. > > How about dividing the problem to smaller blocks then by restoring > parts of the change... Well, what I've done is check out the "bad" tree, reverted every darn commit between there and the "good" tree, and then reverted the reverts so I have a nice merge-free line and don't have to remember to think backward. (probably sounds silly to git-foo masters) I'll try bisecting that in the a.m. and see what happens. -Mike