From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964946AbWL1G2P (ORCPT ); Thu, 28 Dec 2006 01:28:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964939AbWL1G2P (ORCPT ); Thu, 28 Dec 2006 01:28:15 -0500 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:2413 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S964946AbWL1G2O (ORCPT ); Thu, 28 Dec 2006 01:28:14 -0500 Date: Wed, 27 Dec 2006 22:27:48 -0800 (PST) Message-Id: <20061227.222748.74746488.davem@davemloft.net> To: kenneth.w.chen@intel.com Cc: torvalds@osdl.org, ranma@tdiedrich.de, gordonfarquharson@gmail.com, tbm@cyrius.com, a.p.zijlstra@chello.nl, andrei.popa@i-neo.ro, akpm@osdl.org, hugh@veritas.com, nickpiggin@yahoo.com.au, arjan@infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: fix page_mkclean_one From: David Miller In-Reply-To: <000101c72a46$ee2296b0$bc84030a@amr.corp.intel.com> References: <000001c72a44$c3da12e0$bc84030a@amr.corp.intel.com> <000101c72a46$ee2296b0$bc84030a@amr.corp.intel.com> X-Mailer: Mew version 5.1.52 on Emacs 21.4 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: "Chen, Kenneth W" Date: Wed, 27 Dec 2006 22:10:52 -0800 > Chen, Kenneth wrote on Wednesday, December 27, 2006 9:55 PM > > Linus Torvalds wrote on Wednesday, December 27, 2006 7:05 PM > > > On Wed, 27 Dec 2006, David Miller wrote: > > > > > > > > > > I still don't see _why_, though. But maybe smarter people than me can see > > > > > it.. > > > > > > > > FWIW this program definitely triggers the bug for me. > > > > > > Ok, now that I have something simple to do repeatable stuff with, I can > > > say what the pattern is.. It's not all that surprising, but it's still > > > worth just stating for the record. > > > > > > Running the test code, git bisect points its finger at this commit. Reverting > > this commit on top of 2.6.20-rc2 doesn't trigger the bug from the test code. > > > > edc79b2a46ed854595e40edcf3f8b37f9f14aa3f is first bad commit > > commit edc79b2a46ed854595e40edcf3f8b37f9f14aa3f > > Author: Peter Zijlstra > > Date: Mon Sep 25 23:30:58 2006 -0700 > > > > [PATCH] mm: balance dirty pages > > > > Now that we can detect writers of shared mappings, throttle them. Avoids OOM > > by surprise. > > > Oh, never mind :-( I just didn't create enough write out pressure when > test this. I just saw bug got triggered on a kernel I previously thought > was OK. Besides, I'm pretty sure that from the Debian bug entry it's been established that the dirty-page tracking changes from a few releases ago introduced this problem.