From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id B722C6B004D for ; Thu, 22 Oct 2009 10:47:12 -0400 (EDT) Received: by qyk14 with SMTP id 14so5322240qyk.11 for ; Thu, 22 Oct 2009 07:47:11 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1256221356-26049-1-git-send-email-mel@csn.ul.ie> References: <1256221356-26049-1-git-send-email-mel@csn.ul.ie> Date: Thu, 22 Oct 2009 17:47:10 +0300 Message-ID: <84144f020910220747nba30d8bkc83c2569da79bd7c@mail.gmail.com> Subject: Re: [PATCH 0/5] Candidate fix for increased number of GFP_ATOMIC failures V2 From: Pekka Enberg Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: Frans Pop , Jiri Kosina , Sven Geggus , Karol Lewandowski , Tobias Oetiker , "Rafael J. Wysocki" , David Miller , Reinette Chatre , Kalle Valo , David Rientjes , KOSAKI Motohiro , Mohamed Abbas , Jens Axboe , "John W. Linville" , Bartlomiej Zolnierkiewicz , Greg Kroah-Hartman , Stephan von Krawczynski , Kernel Testers List , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "linux-mm@kvack.org\"" , akpm@linux-foundation.org, cl@linux-foundation.org, torvalds@linux-foundation.org List-ID: On Thu, Oct 22, 2009 at 5:22 PM, Mel Gorman wrote: > Test 1: Verify your problem occurs on 2.6.32-rc5 if you can > > Test 2: Apply the following two patches and test again > > =A01/5 page allocator: Always wake kswapd when restarting an allocation a= ttempt after direct reclaim failed > =A02/5 page allocator: Do not allow interrupts to use ALLOC_HARDER These are pretty obvious bug fixes and should go to linux-next ASAP IMHO. > Test 5: If things are still screwed, apply the following > =A05/5 Revert 373c0a7e, 8aa7e847: Fix congestion_wait() sync/async vs rea= d/write confusion > > =A0 =A0 =A0 =A0Frans Pop reports that the bulk of his problems go away wh= en this > =A0 =A0 =A0 =A0patch is reverted on 2.6.31. There has been some confusion= on why > =A0 =A0 =A0 =A0exactly this patch was wrong but apparently the conversion= was not > =A0 =A0 =A0 =A0complete and further work was required. It's unknown if al= l the > =A0 =A0 =A0 =A0necessary work exists in 2.6.31-rc5 or not. If there are s= till > =A0 =A0 =A0 =A0allocation failures and applying this patch fixes the prob= lem, > =A0 =A0 =A0 =A0there are still snags that need to be ironed out. As explained by Jens Axboe, this changes timing but is not the source of the OOMs so the revert is bogus even if it "helps" on some workloads. IIRC the person who reported the revert to help things did report that the OOMs did not go away, they were simply harder to trigger with the revert. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org