From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx192.postini.com [74.125.245.192]) by kanga.kvack.org (Postfix) with SMTP id 88F0A6B002B for ; Mon, 3 Dec 2012 03:26:42 -0500 (EST) Message-ID: <50BC6314.7060106@leemhuis.info> Date: Mon, 03 Dec 2012 09:30:12 +0100 From: Thorsten Leemhuis MIME-Version: 1.0 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: owner-linux-mm@kvack.org List-ID: 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 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 -- 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