From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f70.google.com (mail-wm0-f70.google.com [74.125.82.70]) by kanga.kvack.org (Postfix) with ESMTP id E13836B025F for ; Wed, 11 May 2016 03:38:16 -0400 (EDT) Received: by mail-wm0-f70.google.com with SMTP id e201so34283335wme.1 for ; Wed, 11 May 2016 00:38:16 -0700 (PDT) Received: from mail-wm0-f67.google.com (mail-wm0-f67.google.com. [74.125.82.67]) by mx.google.com with ESMTPS id d2si7639012wjl.68.2016.05.11.00.38.15 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 11 May 2016 00:38:15 -0700 (PDT) Received: by mail-wm0-f67.google.com with SMTP id n129so7696481wmn.1 for ; Wed, 11 May 2016 00:38:15 -0700 (PDT) Date: Wed, 11 May 2016 09:38:14 +0200 From: Michal Hocko Subject: Re: mm: pages are not freed from lru_add_pvecs after process termination Message-ID: <20160511073814.GD16677@dhcp22.suse.cz> References: <5720F2A8.6070406@intel.com> <20160428143710.GC31496@dhcp22.suse.cz> <20160502130006.GD25265@dhcp22.suse.cz> <20160504203643.GI21490@dhcp22.suse.cz> <20160505072122.GA4386@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: "Odzioba, Lukasz" Cc: "Hansen, Dave" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "Shutemov, Kirill" , "Anaczkowski, Lukasz" On Thu 05-05-16 17:25:07, Odzioba, Lukasz wrote: > On Thu 05-05-16 09:21:00, Michal Hocko wrote: > > OK, it wasn't that tricky afterall. Maybe I have missed something but > > the following should work. Or maybe the async nature of flushing turns > > out to be just impractical and unreliable and we will end up skipping > > THP (or all compound pages) for pcp LRU add cache. Let's see... > > Initially this issue was found on RH's 3.10.x kernel, but now I am using > 4.6-rc6. > > In overall it does help and under heavy load it is slightly better than the > second patch. Unfortunately I am still able to hit 10-20% oom kills with it - > (went down from 30-50%) partially due to earlier vmstat_update call > - it went up to 25-25% with this patch below: This simply shows that this is not a viable option. So I guess we really want to rather skip THP (compound pages) from LRU add pcp cache. Thanks for your effort and testing! -- 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