From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965955AbXCPVQE (ORCPT ); Fri, 16 Mar 2007 17:16:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965953AbXCPVQD (ORCPT ); Fri, 16 Mar 2007 17:16:03 -0400 Received: from mail05.syd.optusnet.com.au ([211.29.132.186]:51205 "EHLO mail05.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965954AbXCPVQA (ORCPT ); Fri, 16 Mar 2007 17:16:00 -0400 From: Con Kolivas To: "Chris Friesen" Subject: Re: [PATCH][RSDL-mm 4/6] sched: dont renice kernel threads Date: Sat, 17 Mar 2007 08:29:47 +1100 User-Agent: KMail/1.9.5 Cc: linux kernel mailing list , ck list , Andrew Morton , Ingo Molnar References: <200703170054.08641.kernel@kolivas.org> <45FAB458.2080304@nortel.com> In-Reply-To: <45FAB458.2080304@nortel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200703170829.47810.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Saturday 17 March 2007 02:14, Chris Friesen wrote: > Con Kolivas wrote: > > The practice of renicing kernel threads to negative nice values is of > > questionable benefit at best, and at worst leads to larger latencies when > > kernel threads are busy on behalf of other tasks. > > What about the priority implications of the renicing? It seems a bit > iffy letting kernel threads compete for cpu time on an equal basis with > your default shell. Lots of things we do because we just assume they're a good idea without any evidence. Renicing kernel threads was always considered a good idea on this basis. I'm certain noone has ever proven that it's a good thing though. Either way, the latest version of rsdl is robust enough that it works fine with reniced kernel threads if you still believe that's advantageous. This is definitely open for discussion/opinion. -- -ck