From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753447Ab2LCI0o (ORCPT ); Mon, 3 Dec 2012 03:26:44 -0500 Received: from basicbox7.server-home.net ([195.137.212.29]:49419 "EHLO basicbox7.server-home.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751678Ab2LCI0n (ORCPT ); Mon, 3 Dec 2012 03:26:43 -0500 Message-ID: <50BC6314.7060106@leemhuis.info> Date: Mon, 03 Dec 2012 09:30:12 +0100 From: Thorsten Leemhuis User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Johannes Weiner CC: Mel Gorman , Andrew Morton , Linus Torvalds , Rik van Riel , George Spelvin , Johannes Hirte , Tomas Racek , Jan Kara , Dave Hansen , Josh Boyer , Valdis Kletnieks , Jiri Slaby , Zdenek Kabelac , Bruno Wolff III , linux-mm , Linux Kernel Mailing List , John Ellson Subject: Re: kswapd craziness in 3.7 References: <20121127214928.GA20253@cmpxchg.org> <50B5387C.1030005@redhat.com> <20121127222637.GG2301@cmpxchg.org> <20121128101359.GT8218@suse.de> <20121128145215.d23aeb1b.akpm@linux-foundation.org> <20121128235412.GW8218@suse.de> <50B77F84.1030907@leemhuis.info> <20121129170512.GI2301@cmpxchg.org> <50B8A8E7.4030108@leemhuis.info> <20121201004520.GK2301@cmpxchg.org> In-Reply-To: <20121201004520.GK2301@cmpxchg.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! Johannes Weiner wrote on 01.12.2012 01:45: > On Fri, Nov 30, 2012 at 01:39:03PM +0100, Thorsten Leemhuis wrote: >> /me wonders how to elegantly get out of his man-in-the-middle position > You control the mighty koji :-) Something even a journalist can ;-) > But seriously, this is very helpful, thank you! Np; BTW, in case anybody here on LKML cares: I started maintaining a side repo (PPA in ubuntu speak) a few weeks ago that offers kernel vanilla builds (mainline and stable) for the Fedora 17 and 18; see https://fedoraproject.org/wiki/Kernel_Vanilla_Repositories for details. It's not as good and up2date yet as I would like it, but one has to start somewhere. Back to topic: > John now also Cc'd directly. > >> John was able to reproduce the problem quickly with a kernel that >> contained the patch from your mail. For details see > > [stripped: all the glory details of what likely went wrong and lead > to the problem john sees or saw] > > --- > From: Johannes Weiner > Subject: [patch] mm: vmscan: do not keep kswapd looping forever due > to individual uncompactable zones > > When a zone meets its high watermark and is compactable in case of > higher order allocations, it contributes to the percentage of the > node's memory that is considered balanced. > [...] FYI: I built a kernel with that patch. I've been running on my x86_64 machine at home over the weekend and everything was working fine (just as without the patch). John gave it a quick try and in https://bugzilla.redhat.com/show_bug.cgi?id=866988#c57 reported: """ I just installed kernel-3.7.0-0.rc7.git1.2.van.main.knurd.kswap.4.fc18.i686 and ran my usual load that triggers the problem. OK so far. I'll check again in 24hours, but looking good so far. """ BTW, I built that kernel without the patch you mentioned in http://thread.gmane.org/gmane.linux.kernel.mm/90911/focus=91153 ("buffer_heads_over_limit can put kswapd into reclaim, but it's ignored [...]) It looked to me like that patch was only meant for debugging. Let me know if that was wrong. Ohh, and I didn't update to a fresher mainline checkout yet to make sure the base for John's testing didn't change. CU Thorsten