Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1946684AbWKAIB3 (ORCPT ); Wed, 1 Nov 2006 03:01:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1946686AbWKAIB3 (ORCPT ); Wed, 1 Nov 2006 03:01:29 -0500 Received: from mailhub.sw.ru ([195.214.233.200]:39781 "EHLO relay.sw.ru") by vger.kernel.org with ESMTP id S1946684AbWKAIB2 (ORCPT ); Wed, 1 Nov 2006 03:01:28 -0500 Message-ID: <45485357.6050403@openvz.org> Date: Wed, 01 Nov 2006 10:57:11 +0300 From: Pavel Emelianov User-Agent: Thunderbird 1.5 (X11/20060317) MIME-Version: 1.0 To: Dave Hansen CC: Pavel Emelianov , balbir@in.ibm.com, vatsa@in.ibm.com, dev@openvz.org, sekharan@us.ibm.com, ckrm-tech@lists.sourceforge.net, linux-kernel@vger.kernel.org, pj@sgi.com, matthltc@us.ibm.com, dipankar@in.ibm.com, rohitseth@google.com, menage@google.com Subject: Re: [ckrm-tech] RFC: Memory Controller References: <20061030103356.GA16833@in.ibm.com> <4545D51A.1060808@in.ibm.com> <4546212B.4010603@openvz.org> <454638D2.7050306@in.ibm.com> <45470DF4.70405@openvz.org> <1162314249.28876.120.camel@localhost.localdomain> In-Reply-To: <1162314249.28876.120.camel@localhost.localdomain> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1115 Lines: 28 Dave Hansen wrote: > On Tue, 2006-10-31 at 11:48 +0300, Pavel Emelianov wrote: >> If memory is considered to be unreclaimable then actions should be >> taken at mmap() time, not later! Rejecting mmap() is the only way to >> limit user in unreclaimable memory consumption. > > I don't think this is necessarily true. Today, if a kernel exceeds its > allocation limits (runs out of memory) it gets killed. Doing the > limiting at mmap() time instead of fault time will keep a sparse memory > applications from even being able to run. If limiting _every_ mapping it will, but when limiting only "private" mappings - no problems at all. BC code lives for more than 3 years already and no claims from users on this question yet. > Now, failing an mmap() is a wee bit more graceful than a SIGBUS, but it > certainly introduces its own set of problems. > > -- Dave > > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/