Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752308AbXE3EIJ (ORCPT ); Wed, 30 May 2007 00:08:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751526AbXE3EH4 (ORCPT ); Wed, 30 May 2007 00:07:56 -0400 Received: from omta04ps.mx.bigpond.com ([144.140.83.156]:17305 "EHLO omta04ps.mx.bigpond.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751480AbXE3EHz (ORCPT ); Wed, 30 May 2007 00:07:55 -0400 Message-ID: <465CF893.10906@bigpond.net.au> Date: Wed, 30 May 2007 14:07:47 +1000 From: Peter Williams User-Agent: Thunderbird 1.5.0.10 (X11/20070302) MIME-Version: 1.0 To: William Lee Irwin III CC: vatsa@in.ibm.com, Kirill Korotaev , Nick Piggin , tingy@cs.umass.edu, ckrm-tech@lists.sourceforge.net, Balbir Singh , efault@gmx.de, kernel@kolivas.org, linux-kernel@vger.kernel.org, tong.n.li@intel.com, containers@lists.osdl.org, Ingo Molnar , torvalds@linux-foundation.org, akpm@linux-foundation.org, Guillaume Chazarain Subject: Re: [ckrm-tech] [RFC] [PATCH 0/3] Add group fairness to CFS References: <20070525082951.GA25280@elte.hu> <4656DF0C.9090306@sw.ru> <20070525153450.GA4679@in.ibm.com> <46570C70.4050209@sw.ru> <20070525180850.GA26884@in.ibm.com> <46577CA6.8000807@bigpond.net.au> <20070526154112.GA31925@holomorphy.com> <4658DF0F.5020208@bigpond.net.au> <20070529104805.GC31925@holomorphy.com> <465CC0B8.8050507@bigpond.net.au> <20070530024815.GA6909@holomorphy.com> In-Reply-To: <20070530024815.GA6909@holomorphy.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Authentication-Info: Submitted using SMTP AUTH PLAIN at oaamta04ps.mx.bigpond.com from [60.231.45.148] using ID pwil3058@bigpond.net.au at Wed, 30 May 2007 04:07:52 +0000 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1479 Lines: 30 William Lee Irwin III wrote: > On Wed, May 30, 2007 at 10:09:28AM +1000, Peter Williams wrote: >> So what you're saying is that you think dynamic priority (or its >> equivalent) should be used for load balancing instead of static priority? > > It doesn't do much in other schemes, but when fairness is directly > measured by the dynamic priority, it is a priori more meaningful. > This is not to say the net effect of using it is so different. I suspect that while it's probably theoretically better it wouldn't make much difference on a real system (probably not enough to justify any extra complexity if there were any). The exception might be on systems where there were lots of CPU intensive tasks that used relatively large chunks of CPU each time they were runnable which would give the load balancer a more stable load to try and balance. It might be worth the extra effort to get it exactly right on those systems. On most normal systems this isn't the case and the load balancer is always playing catch up to a constantly changing scenario. Peter -- Peter Williams pwil3058@bigpond.net.au "Learning, n. The kind of ignorance distinguishing the studious." -- Ambrose Bierce - 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/