From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yk0-f173.google.com (mail-yk0-f173.google.com [209.85.160.173]) by kanga.kvack.org (Postfix) with ESMTP id BDE286B0035 for ; Tue, 21 Jan 2014 23:53:11 -0500 (EST) Received: by mail-yk0-f173.google.com with SMTP id 20so4961167yks.4 for ; Tue, 21 Jan 2014 20:53:11 -0800 (PST) Received: from mail-gg0-x22f.google.com (mail-gg0-x22f.google.com [2607:f8b0:4002:c02::22f]) by mx.google.com with ESMTPS id r4si9065399yhg.235.2014.01.21.20.53.10 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 21 Jan 2014 20:53:10 -0800 (PST) Received: by mail-gg0-f175.google.com with SMTP id c2so2916577ggn.34 for ; Tue, 21 Jan 2014 20:53:10 -0800 (PST) Date: Tue, 21 Jan 2014 20:53:07 -0800 (PST) From: David Rientjes Subject: Re: [patch] mm: oom_kill: revert 3% system memory bonus for privileged tasks In-Reply-To: <20140116070709.GM6963@cmpxchg.org> Message-ID: References: <20140115234308.GB4407@cmpxchg.org> <20140116070709.GM6963@cmpxchg.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Johannes Weiner Cc: Andrew Morton , Michal Hocko , linux-mm@kvack.org, linux-kernel@vger.kernel.org On Thu, 16 Jan 2014, Johannes Weiner wrote: > > Unfortunately, I think this could potentially be too much of a bonus. On > > your same 32GB machine, if a root process is using 18GB and a user process > > is using 14GB, the user process ends up getting selected while the current > > discount of 3% still selects the root process. > > > > I do like the idea of scaling this bonus depending on points, however. I > > think it would be better if we could scale the discount but also limit it > > to some sane value. > > I just reverted to the /= 4 because we had that for a long time and it > seemed to work. I don't really mind either way as long as we get rid > of that -3%. Do you have a suggestion? > How about simply using 3% of the root process's points so that root processes get some bonus compared to non-root processes with the same memory usage and it's scaled to the usage rather than amount of available memory? So rather than points /= 4, we do if (has_capability_noaudit(p, CAP_SYS_ADMIN)) points -= (points * 3) / 100; instead. Sound good? -- 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