From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752802AbdBJIyJ (ORCPT ); Fri, 10 Feb 2017 03:54:09 -0500 Received: from mx2.suse.de ([195.135.220.15]:39576 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751949AbdBJIyI (ORCPT ); Fri, 10 Feb 2017 03:54:08 -0500 Date: Fri, 10 Feb 2017 09:52:32 +0100 From: Michal Hocko To: Yisheng Xie Cc: Vlastimil Babka , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Tetsuo Handa , Hanjun Guo Subject: Re: [RFC] 3.10 kernel- oom with about 24G free memory Message-ID: <20170210085232.GD10893@dhcp22.suse.cz> References: <9a22aefd-dfb8-2e4c-d280-fc172893bcb4@huawei.com> <20170209132628.GI10257@dhcp22.suse.cz> <20170209134131.GJ10257@dhcp22.suse.cz> <20170210070930.GA9346@dhcp22.suse.cz> <7d01fea5-66d6-b6ac-918d-19ec8a15dbaf@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7d01fea5-66d6-b6ac-918d-19ec8a15dbaf@huawei.com> User-Agent: Mutt/1.6.0 (2016-04-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 10-02-17 16:48:58, Yisheng Xie wrote: > Hi Michal, > > Thanks for comment! > On 2017/2/10 15:09, Michal Hocko wrote: > > On Fri 10-02-17 09:13:58, Yisheng Xie wrote: > >> hi Michal, > >> Thanks for your comment. > >> > >> On 2017/2/9 21:41, Michal Hocko wrote: [...] > >>>> OK, so this is a memcg OOM killer which panics because the configuration > >>>> says so. The OOM report doesn't say so and that is the bug. dump_header > >>>> is memcg aware and mem_cgroup_out_of_memory initializes oom_control > >>>> properly. Is this Vanilla kernel? > >> > >> That means we should raise the limit of that memcg to avoid memcg OOM killer, right? > > > > Why do you configure the system to panic on memcg OOM in the first > > place. This is a wrong thing to do in 99% of cases. > > For our production think it should use reboot to recovery the system when OOM, > instead of killing user's key process. Maybe not the right thing. I can understand that for the global oom killer but not for memcg. You can recover the oom even without killing any process. You can simply increase the limit from the userspace when the oom event is triggered. Trigerring the panic on memcg oom killer is both dangerous and most probably something you do not want. -- Michal Hocko SUSE Labs