From mboxrd@z Thu Jan 1 00:00:00 1970 From: Justin Piszcz Subject: Re: [Bug #13648] nfsd: page allocation failure Date: Tue, 30 Jun 2009 04:05:02 -0400 (EDT) Message-ID: References: <5Hhc7UkUKEO.A.KGF.HjASKB@chimera> Mime-Version: 1.0 Return-path: In-Reply-To: Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: TEXT/PLAIN; charset="us-ascii"; format="flowed" Content-Transfer-Encoding: 7bit To: David Rientjes Cc: Linux Kernel Mailing List , Kernel Testers List , "Rafael J. Wysocki" , Rik van Riel On Mon, 29 Jun 2009, David Rientjes wrote: > On Mon, 29 Jun 2009, Rafael J. Wysocki wrote: > >> This message has been generated automatically as a part of a report >> of regressions introduced between 2.6.29 and 2.6.30. >> >> The following bug entry is on the current list of known regressions >> introduced between 2.6.29 and 2.6.30. Please verify if it still should >> be listed and let me know (either way). >> >> >> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=13648 >> Subject : nfsd: page allocation failure >> Submitter : Justin Piszcz >> Date : 2009-06-22 12:08 (7 days old) >> References : http://lkml.org/lkml/2009/6/22/309 >> > > I'd be interested to hear from Justin if reducing > /proc/sys/vm/dirty_background_ratio as I earlier suggested helps. > > ZONE_NORMAL isn't much larger than ZONE_DMA32 on this machine and both > lowmem zones have an abundance of free memory which suggests pdflush's > ratio isn't being met to commence background writeout while at the same > time ZONE_NORMAL is being depleted as the result of constant nfs > GFP_ATOMIC allocations that cannot try direct reclaim. > Hello, http://patchwork.kernel.org/patch/30960/ "It's funny, though, that the problem that originally started this thread was quickly diagnosed because of these messages. As far as I know, my suggestion to increase /proc/sys/vm/dirty_background_ratio to kick pdflush earlier has prevented the slab allocation failures and not required delayed acks for nfsd." -- The current value is 10, what value do you suggest I try? $ cat /proc/sys/vm/dirty_background_ratio 10 Justin.