From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759249AbXISXUr (ORCPT ); Wed, 19 Sep 2007 19:20:47 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754950AbXISXUk (ORCPT ); Wed, 19 Sep 2007 19:20:40 -0400 Received: from mail1.opticatech.com ([63.253.105.122]:21125 "EHLO opticatech.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754601AbXISXUj (ORCPT ); Wed, 19 Sep 2007 19:20:39 -0400 Message-ID: <46F1AEBB.6000809@comcast.net> Date: Wed, 19 Sep 2007 17:20:27 -0600 From: Chris Rigg User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: Ingo Molnar CC: Willy Tarreau , linux-kernel@vger.kernel.org Subject: MAX_RT_PRIO - 1 Highest prio? References: <46EEE498.1080500@comcast.net> <20070918050043.GE10199@1wt.eu> <20070918062606.GA5138@elte.hu> In-Reply-To: <20070918062606.GA5138@elte.hu> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 19 Sep 2007 23:20:35.0360 (UTC) FILETIME=[AE7B1200:01C7FB13] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hello, First, I'm assuming that if I want my task to have the HIGHEST priority in the system (i.e. preempt any other task whenever it is put into the ready queue (assuming I have preemption turned on/configured)), I use sched_setscheduler (...) and use the sched_priority in sched_param for MAX_RT_PRIO -1. Is this correct? Second, assuming that MAX_RT_PRIO-1 is the highest, would it be bad on an SMP/Hyperthreading system (that's using the migration thread balancing in 2.6.20.7) to set a task's priority to MAX_RT_PRIO -1 given the fact that the migration threads are already set to MAX_RT_PRIO -1? Should I be setting my task's prio to MAX_RT_PRIO-2 to not interfere with the load balancing? Thanks, Chris