From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261695AbVFPPtV (ORCPT ); Thu, 16 Jun 2005 11:49:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261696AbVFPPtU (ORCPT ); Thu, 16 Jun 2005 11:49:20 -0400 Received: from zcars04f.nortelnetworks.com ([47.129.242.57]:60107 "EHLO zcars04f.nortelnetworks.com") by vger.kernel.org with ESMTP id S261695AbVFPPtP (ORCPT ); Thu, 16 Jun 2005 11:49:15 -0400 Message-ID: <42B19F65.6000102@nortel.com> Date: Thu, 16 Jun 2005 09:48:53 -0600 X-Sybari-Space: 00000000 00000000 00000000 00000000 From: Chris Friesen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040115 X-Accept-Language: en-us, en MIME-Version: 1.0 To: =?ISO-8859-1?Q?Patrik_H=E4gglund?= CC: linux-kernel@vger.kernel.org Subject: Re: SCHED_RR/SCHED_FIFO and kernel threads? References: <42B199FF.5010705@bredband.net> In-Reply-To: <42B199FF.5010705@bredband.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Patrik Hägglund wrote: > Kernel threads seems to generally be scheduled in the SCHED_OTHER class > (with the 'migration' thread as an exception). This is on purpose. The idea is that realtime processes get all the time they request. If the kernel threads are interrupting the realtime app, then the latency of the realtime app is degraded. > As I see it, "kernel activity" shall not be starved by user-space > processes. Therefore, I was very suprised by this behaviour when I saw > it in 2.6.11. If you want specific kernel threads to take priority, you can always manually make then SCHED_RR/SCHED_FIFO yourself. Chris