From mboxrd@z Thu Jan 1 00:00:00 1970 From: Corrado Zoccolo Subject: Re: still getting allocation failures (was Re: [PATCH] vmscan: Stop kswapd waiting on congestion when the min watermark is not being met V2) Date: Thu, 3 Dec 2009 21:26:00 +0100 Message-ID: <4e5e476b0912031226i5b0e6cf9hdfd5519182ccdefa@mail.gmail.com> References: <20091113142608.33B9.A69D9226@jp.fujitsu.com> <20091113135443.GF29804@csn.ul.ie> <20091114023138.3DA5.A69D9226@jp.fujitsu.com> <20091113181557.GM29804@csn.ul.ie> <2f11576a0911131033w4a9e6042k3349f0be290a167e@mail.gmail.com> <20091113200357.GO29804@csn.ul.ie> <20091202113241.GC1457@csn.ul.ie> Mime-Version: 1.0 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=+/+gBWgmHZmFomi1NIOVJi5JitmiYaC2BCCG4sbEeGw=; b=v8CrXurbtjX5KhdFxwFTQFvgvZASEEZjTT/FnEShV7qkEom1OVirtdh/E8b1+Z3zrt pVDhHpZX4cdeR/GiP9MiA5tWULbwqnVHmydlUwYBcq+oQYDHlKUwJH7ifxpKNAkyOHbH ibOnWcm7U/6chcFnf48To5vOEkxnzaHJn5uxw= In-Reply-To: Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="utf-8" To: Tobias Oetiker Cc: Mel Gorman , Andrew Morton , KOSAKI Motohiro , Frans Pop , Jiri Kosina , Sven Geggus , Karol Lewandowski , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org" , Pekka Enberg , Rik van Riel , Christoph Lameter , Stephan von Krawczynski , "Rafael J. Wysocki" , Kernel Testers List Hi Tobias, does the patch in http://lkml.org/lkml/2009/11/30/301 help with your high order allocation problems? It seems that you have lot of memory, but high order pages do not show = up. The patch should make them more likely to appear. On my machine (that has much less ram than yours), with the patch, I always have order-10 pages available. Corrado On Wed, Dec 2, 2009 at 10:30 PM, Tobias Oetiker wrote= : > Hi Mel, > > Today Mel Gorman wrote: > >> On Sun, Nov 29, 2009 at 08:42:09AM +0100, Tobi Oetiker wrote: >> > Hi Mel, >> > >> > Thursday Tobias Oetiker wrote: >> > > Hi Mel, >> > > >> > > Nov 13 Mel Gorman wrote: >> > > >> > > > The last version has a stupid bug in it. Sorry. >> > > > >> > > > Changelog since V1 >> > > > =C2=A0 o Fix incorrect negation >> > > > =C2=A0 o Rename kswapd_no_congestion_wait to kswapd_skip_conge= stion_wait as >> > > > =C2=A0 =C2=A0 suggested by Rik >> > > > >> > > > If reclaim fails to make sufficient progress, the priority is = raised. >> > > > Once the priority is higher, kswapd starts waiting on congesti= on. =C2=A0However, >> > > > if the zone is below the min watermark then kswapd needs to co= ntinue working >> > > > without delay as there is a danger of an increased rate of GFP= _ATOMIC >> > > > allocation failure. >> > > > >> > > > This patch changes the conditions under which kswapd waits on >> > > > congestion by only going to sleep if the min watermarks are be= ing met. >> > > >> > > I finally got around to test this together with the whole series= on >> > > 2.6.31.6. after running it for a day I have not yet seen a singl= e >> > > order:5 allocation problem ... (while I had several an hour befo= re) >> > >> > > for the record, my kernel is now running with the following >> > > patches: >> > > >> > > patch1:Date: Thu, 12 Nov 2009 19:30:31 +0000 >> > > patch1:Subject: [PATCH 1/5] page allocator: Always wake kswapd w= hen restarting an allocation attempt after direct reclaim failed >> > > >> > > patch2:Date: Thu, 12 Nov 2009 19:30:32 +0000 >> > > patch2:Subject: [PATCH 2/5] page allocator: Do not allow interru= pts to use ALLOC_HARDER >> > > >> > > patch3:Date: Thu, 12 Nov 2009 19:30:33 +0000 >> > > patch3:Subject: [PATCH 3/5] page allocator: Wait on both sync an= d async congestion after direct reclaim >> > > >> > > patch4:Date: Thu, 12 Nov 2009 19:30:34 +0000 >> > > patch4:Subject: [PATCH 4/5] vmscan: Have kswapd sleep for a shor= t interval and double check it should be asleep >> > > >> > > patch5:Date: Fri, 13 Nov 2009 20:03:57 +0000 >> > > patch5:Subject: [PATCH] vmscan: Stop kswapd waiting on congestio= n when the min watermark is not being met V2 >> > > >> > > patch6:Date: Tue, 17 Nov 2009 10:34:21 +0000 >> > > patch6:Subject: [PATCH] vmscan: Have kswapd sleep for a short in= terval and double check it should be asleep fix 1 >> > > >> > I have now been running the new kernel for a few days and I am >> > sorry to report that about a day after booting the allocation >> > failures started showing again. More order:4 instead of order:5 ..= =2E >> > >> >> Why has the order changed? > > ? no idea ... the order has changed after applying the patches > cited above. > >> Also, what allocator were you using in 2.6.30 and 2.6.31.6, SLAB or >> SLUB? Did you happen to change them when upgrading the kernel? > > I have been and still am using SLUB =C2=A0... > > cheers > tobi > > > -- > Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten, Switzerlan= d > http://it.oetiker.ch tobi-7K0TWYW2a3pyDzI6CaY1VQ@public.gmane.org ++41 62 775 9902 / sb: -9900 > -- > To unsubscribe from this list: send the line "unsubscribe linux-kerne= l" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at =C2=A0http://vger.kernel.org/majordomo-info.ht= ml > Please read the FAQ at =C2=A0http://www.tux.org/lkml/ > --=20 _______________________________________________________________________= ___ dott. Corrado Zoccolo mailto:czoccolo-Re5JQEeQqe8@public.gmane.org= m PhD - Department of Computer Science - University of Pisa, Italy -----------------------------------------------------------------------= --- The self-confidence of a warrior is not the self-confidence of the aver= age man. The average man seeks certainty in the eyes of the onlooker and ca= lls that self-confidence. The warrior seeks impeccability in his own eyes a= nd calls that humbleness. Tales of Power - C. Castaneda