From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 013476B0012 for ; Tue, 14 Jun 2011 08:33:10 -0400 (EDT) Received: by pvc12 with SMTP id 12so3246867pvc.14 for ; Tue, 14 Jun 2011 05:33:08 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20110614101047.GG6371@cmpxchg.org> References: <20110614101047.GG6371@cmpxchg.org> From: Andrew Lutomirski Date: Tue, 14 Jun 2011 08:32:48 -0400 Message-ID: Subject: Re: Easy portable testcase! (Re: Kernel falls apart under light memory pressure (i.e. linking vmlinux)) Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Minchan Kim , mgorman@suse.de, KOSAKI Motohiro , aarcange@redhat.com, kamezawa.hiroyu@jp.fujitsu.com, fengguang.wu@intel.com, andi@firstfloor.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, riel@redhat.com On Tue, Jun 14, 2011 at 6:10 AM, Johannes Weiner wrote: > On Sun, May 29, 2011 at 08:28:46PM -0400, Andrew Lutomirski wrote: >> On Sun, May 29, 2011 at 2:28 PM, Minchan Kim wrote: >> >> >> >> It works only if the zone meets high watermark. If allocation is >> >> faster than reclaim(ie, it's true for slow swap device), the zone >> >> would remain congested. >> >> It means swapout would block. >> >> As we see the OOM log, we can know that DMA32 zone can't meet high watermark. >> >> >> >> Does my guessing make sense? >> > >> > Hi Andrew. >> > I got failed your scenario in my machine so could you be willing to >> > test this patch for proving my above scenario? >> > The patch is just revert patch of 0e093d99[do not sleep on the >> > congestion queue...] for 2.6.38.6. >> > I would like to test it for proving my above zone congestion scenario. >> > >> > I did it based on 2.6.38.6 for your easy apply so you must apply it >> > cleanly on vanilla v2.6.38.6. >> > And you have to add !pgdat_balanced and shrink_slab patch. >> >> No, because my laptop just decided that it doesn't like to turn on. :( >> >> I'll test it on my VM on Tuesday and (fingers crossed) on my repaired >> laptop next weekend. > > Any updates on this? > Sorry, got distracted by writing my thesis. This patch (Revert "writeback: do not sleep on the congestion queue if there are no congested BDIs or if significant congestion is not being encountered in the current zone") does not fix the problem; if anything it triggers more easily with the patch (at least in KVM). --Andy -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org