From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751314AbXAQEhJ (ORCPT ); Tue, 16 Jan 2007 23:37:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751515AbXAQEhJ (ORCPT ); Tue, 16 Jan 2007 23:37:09 -0500 Received: from omx1-ext.sgi.com ([192.48.179.11]:40640 "EHLO omx1.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751314AbXAQEhG (ORCPT ); Tue, 16 Jan 2007 23:37:06 -0500 Date: Tue, 16 Jan 2007 20:36:22 -0800 From: Paul Jackson To: Andi Kleen Cc: clameter@sgi.com, akpm@osdl.org, menage@google.com, linux-kernel@vger.kernel.org, nickpiggin@yahoo.com.au, linux-mm@kvack.org, dgc@sgi.com Subject: Re: [RFC 5/8] Make writeout during reclaim cpuset aware Message-Id: <20070116203622.7f1b4e87.pj@sgi.com> In-Reply-To: <200701171528.16854.ak@suse.de> References: <20070116054743.15358.77287.sendpatchset@schroedinger.engr.sgi.com> <200701170907.14670.ak@suse.de> <20070116202056.075c4c03.pj@sgi.com> <200701171528.16854.ak@suse.de> Organization: SGI X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.3; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > With a per node dirty limit ... What would this mean? Lets say we have a simple machine with 4 nodes, cpusets disabled. Lets say all tasks are allowed to use all nodes, no set_mempolicy either. If a task happens to fill up 80% of one node with dirty pages, but we have no dirty pages yet on other nodes, and we have a dirty ratio of 40%, then do we throttle that task's writes? I am surprised you are asking for this, Andi. I would have thought that on no-cpuset systems, the system wide throttling served your needs fine. If not, then I can only guess that is because NUMA mempolicy constraints on allowed nodes are causing the same dirty page problems as cpuset constrained systems -- is that your concern? -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.925.600.0401 From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 16 Jan 2007 20:36:22 -0800 From: Paul Jackson Subject: Re: [RFC 5/8] Make writeout during reclaim cpuset aware Message-Id: <20070116203622.7f1b4e87.pj@sgi.com> In-Reply-To: <200701171528.16854.ak@suse.de> References: <20070116054743.15358.77287.sendpatchset@schroedinger.engr.sgi.com> <200701170907.14670.ak@suse.de> <20070116202056.075c4c03.pj@sgi.com> <200701171528.16854.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andi Kleen Cc: clameter@sgi.com, akpm@osdl.org, menage@google.com, linux-kernel@vger.kernel.org, nickpiggin@yahoo.com.au, linux-mm@kvack.org, dgc@sgi.com List-ID: > With a per node dirty limit ... What would this mean? Lets say we have a simple machine with 4 nodes, cpusets disabled. Lets say all tasks are allowed to use all nodes, no set_mempolicy either. If a task happens to fill up 80% of one node with dirty pages, but we have no dirty pages yet on other nodes, and we have a dirty ratio of 40%, then do we throttle that task's writes? I am surprised you are asking for this, Andi. I would have thought that on no-cpuset systems, the system wide throttling served your needs fine. If not, then I can only guess that is because NUMA mempolicy constraints on allowed nodes are causing the same dirty page problems as cpuset constrained systems -- is that your concern? -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.925.600.0401 -- 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