From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261355AbUBZCSZ (ORCPT ); Wed, 25 Feb 2004 21:18:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261434AbUBZCSZ (ORCPT ); Wed, 25 Feb 2004 21:18:25 -0500 Received: from alt.aurema.com ([203.217.18.57]:61340 "EHLO smtp.sw.oz.au") by vger.kernel.org with ESMTP id S261355AbUBZCSX (ORCPT ); Wed, 25 Feb 2004 21:18:23 -0500 Message-ID: <403D576A.6030900@aurema.com> Date: Thu, 26 Feb 2004 13:18:18 +1100 From: Peter Williams Organization: Aurema Pty Ltd User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.2.1) Gecko/20030225 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Timothy Miller CC: linux-kernel@vger.kernel.org Subject: Re: [RFC][PATCH] O(1) Entitlement Based Scheduler References: <403D3E47.4080501@techsource.com> In-Reply-To: <403D3E47.4080501@techsource.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Timothy Miller wrote: > > In fact, that may be the only "flaw" in your design. It sounds like > your scheduler does an excellent job at fairness with very low overhead. > The only problem with it is that it doesn't determine priority > dynamically. This (i.e. automatic renicing of specified programs) is a good idea but is not really a function that should be undertaken by the scheduler itself. Two possible solutions spring to mind: 1. modify the do_execve() in fs/exec.c to renice tasks when they execute specified binaries 2. have a user space daemon poll running tasks periodically and renice them if they are running specified binaries Both of these solutions have their advantages and disadvantages, are (obviously) complicated than I've made them sound and would require a great deal of care to be taken during their implementation. However, I think that they are both doable. My personal preference would be for the in kernel solution on the grounds of efficiency. Peter -- Dr Peter Williams, Chief Scientist peterw@aurema.com Aurema Pty Limited Tel:+61 2 9698 2322 PO Box 305, Strawberry Hills NSW 2012, Australia Fax:+61 2 9699 9174 79 Myrtle Street, Chippendale NSW 2008, Australia http://www.aurema.com