Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761188AbXLTNTu (ORCPT ); Thu, 20 Dec 2007 08:19:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753959AbXLTNTl (ORCPT ); Thu, 20 Dec 2007 08:19:41 -0500 Received: from metis.extern.pengutronix.de ([83.236.181.26]:56740 "EHLO metis.extern.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754155AbXLTNTk convert rfc822-to-8bit (ORCPT ); Thu, 20 Dec 2007 08:19:40 -0500 From: Juergen Beisert Organization: Pengutronix - Linux Solutions for Science and Industry To: linux-rt-users@vger.kernel.org Date: Thu, 20 Dec 2007 14:18:16 +0100 User-Agent: KMail/1.9.4 Cc: "Jaswinder Singh" , "Remy Bohmer" , "Steven Rostedt" , "Arnaldo Carvalho de Melo" , "Ingo Molnar" , "Darren Hart" , "Sven-Thorsten Dietrich" , LKML References: <20071219194551.315868746@bohmer.net> <3efb10970712200425x4b0ffadcpd2ffa3223eda7b3d@mail.gmail.com> <1985e0f60712200445o4f854cdep6eebf1726737229b@mail.gmail.com> In-Reply-To: <1985e0f60712200445o4f854cdep6eebf1726737229b@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8BIT Content-Disposition: inline Message-Id: <200712201418.17378.jbe@pengutronix.de> X-SA-Exim-Connect-IP: 83.236.181.29 X-SA-Exim-Mail-From: jbe@pengutronix.de Subject: Re: [patch 3/3] Enable setting of IRQ-thread priorities from kernel cmdline. (repost:CC to LKML) X-SA-Exim-Version: 4.2.1 (built Tue, 09 Jan 2007 17:23:22 +0000) X-SA-Exim-Scanned: Yes (on metis.extern.pengutronix.de) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1350 Lines: 33 On Thursday 20 December 2007 13:45, Jaswinder Singh wrote: > On 12/20/07, Remy Bohmer wrote: > > So, Is this a serious requirement? Should this be possible? > > I have noticed this problem: > root@192.168.1.253:~# cat /proc/loadavgrt > 1.00 1.00 1.00 0/52 1158 > root@192.168.1.253:~# cat /proc/loadavg > 0.00 0.00 0.02 1/52 1159 > root@192.168.1.253:~# > > So I am curious, if possible, user can switch softirq-threads or IRQs > RT tasks to non-RT tasks for slow hardware or least important hardware > for NON-RT tasks. So this will improve RT behaviour. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Why? IMHO: Simply decrease the RT priority of less important IRQs or increase all other more important IRQs. IRQs are always more important than other processes in a system, also in non RT systems. Juergen -- Dipl.-Ing. Juergen Beisert | http://www.pengutronix.de ?Pengutronix - Linux Solutions for Science and Industry ? Handelsregister: Amtsgericht Hildesheim, HRA 2686 ? ? ? Vertretung Sued/Muenchen, Germany Phone: +49-8766-939 228 | Fax: +49-5121-206917-9 -- 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/