From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f45.google.com (mail-pa0-f45.google.com [209.85.220.45]) by kanga.kvack.org (Postfix) with ESMTP id 8499D6B0254 for ; Thu, 3 Mar 2016 15:57:32 -0500 (EST) Received: by mail-pa0-f45.google.com with SMTP id fl4so21144081pad.0 for ; Thu, 03 Mar 2016 12:57:32 -0800 (PST) Received: from mail-pf0-x22e.google.com (mail-pf0-x22e.google.com. [2607:f8b0:400e:c00::22e]) by mx.google.com with ESMTPS id p9si400761pfa.74.2016.03.03.12.57.31 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 03 Mar 2016 12:57:31 -0800 (PST) Received: by mail-pf0-x22e.google.com with SMTP id 63so21329525pfe.3 for ; Thu, 03 Mar 2016 12:57:31 -0800 (PST) Date: Thu, 3 Mar 2016 12:57:23 -0800 (PST) From: Hugh Dickins Subject: Re: [PATCH 0/3] OOM detection rework v4 In-Reply-To: <20160303123258.GE26202@dhcp22.suse.cz> Message-ID: References: <1450203586-10959-1-git-send-email-mhocko@kernel.org> <20160203132718.GI6757@dhcp22.suse.cz> <20160229203502.GW16930@dhcp22.suse.cz> <20160301133846.GF9461@dhcp22.suse.cz> <20160303123258.GE26202@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Hugh Dickins , Vlastimil Babka , Joonsoo Kim , Andrew Morton , Linus Torvalds , Johannes Weiner , Mel Gorman , David Rientjes , Tetsuo Handa , Hillf Danton , KAMEZAWA Hiroyuki , linux-mm@kvack.org, LKML On Thu, 3 Mar 2016, Michal Hocko wrote: > On Thu 03-03-16 01:54:43, Hugh Dickins wrote: > > On Tue, 1 Mar 2016, Michal Hocko wrote: > [...] > > > So I have tried the following: > > > diff --git a/mm/compaction.c b/mm/compaction.c > > > index 4d99e1f5055c..7364e48cf69a 100644 > > > --- a/mm/compaction.c > > > +++ b/mm/compaction.c > > > @@ -1276,6 +1276,9 @@ static unsigned long __compaction_suitable(struct zone *zone, int order, > > > alloc_flags)) > > > return COMPACT_PARTIAL; > > > > > > + if (order <= PAGE_ALLOC_COSTLY_ORDER) > > > + return COMPACT_CONTINUE; > > > + > > > > I gave that a try just now, but it didn't help me: OOMed much sooner, > > after doing half as much work. I think I exaggerated: sooner, but not _much_ sooner; and I cannot see now what I based that estimate of "half as much work" on. > > I do not have an explanation why it would cause oom sooner but this > turned out to be incomplete. There is another wmaark check deeper in the > compaction path. Could you try the one from > http://lkml.kernel.org/r/20160302130022.GG26686@dhcp22.suse.cz I've now added that in: it corrects the "sooner", but does not make any difference to the fact of OOMing for me. Hugh > > I will try to find a machine with more CPUs and try to reproduce this in > the mean time. > > I will also have a look at the data you have collected. > -- > Michal Hocko > SUSE Labs -- 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