From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753498AbaCFVIQ (ORCPT ); Thu, 6 Mar 2014 16:08:16 -0500 Received: from mail-pb0-f52.google.com ([209.85.160.52]:37385 "EHLO mail-pb0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752099AbaCFVIM (ORCPT ); Thu, 6 Mar 2014 16:08:12 -0500 Date: Thu, 6 Mar 2014 13:08:10 -0800 (PST) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Tejun Heo cc: Andrew Morton , Johannes Weiner , Michal Hocko , KAMEZAWA Hiroyuki , Christoph Lameter , Pekka Enberg , Mel Gorman , Oleg Nesterov , Rik van Riel , Jianguo Wu , Tim Hockin , linux-kernel@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [patch 00/11] userspace out of memory handling In-Reply-To: <20140306205911.GG14033@htj.dyndns.org> Message-ID: References: <20140306204923.GF14033@htj.dyndns.org> <20140306205911.GG14033@htj.dyndns.org> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 6 Mar 2014, Tejun Heo wrote: > > This includes system oom handling alongside memcg oom handling. If you > > have specific objections, please let us know, thanks! > > Umm, that wasn't the bulk of objection, was it? We were discussion > the whole premise of userland oom handling and the conclusion, at > best, was that you couldn't show that it was actually necessary and > most other people disliked the idea. I'm not sure how you reach that conclusion: it's necessary because any process handling the oom condition will need memory to do anything useful. How else would a process that is handling a system oom condition, for example, be able to obtain a list of processes, check memory usage, issue a kill, do any logging, collect heap or smaps samples, or signal processes to throttle incoming requests without having access to memory itself? The system is oom. > Just changing a part of it and > resubmitting doesn't really change the whole situation. If you want > to continue the discussion on the basic approach, please do continue > that on the original thread so that we don't lose the context. I'm > gonna nack the respective patches so that they don't get picked up by > accident for now. > This is going to be discussed at the LSF/mm conference, I believe it would be helpful to have an actual complete patchset proposed so that it can be discussed properly. I feel no need to refer to an older patchset that would not apply and did not include all the support necessary for handling oom conditions.