Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263408AbTIGRiy (ORCPT ); Sun, 7 Sep 2003 13:38:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263376AbTIGRhg (ORCPT ); Sun, 7 Sep 2003 13:37:36 -0400 Received: from static-ctb-210-9-247-166.webone.com.au ([210.9.247.166]:32014 "EHLO chimp.local.net") by vger.kernel.org with ESMTP id S263388AbTIGRhD (ORCPT ); Sun, 7 Sep 2003 13:37:03 -0400 Message-ID: <3F5B6CB9.9050408@cyberone.com.au> Date: Mon, 08 Sep 2003 03:36:57 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20030827 Debian/1.4-3 X-Accept-Language: en MIME-Version: 1.0 To: John Yau CC: linux-kernel@vger.kernel.org Subject: Re: [PATCH] Minor scheduler fix to get rid of skipping in xmms References: <000201c374c8$1124ee20$f40a0a0a@Aria> <3F5ABE90.2040003@cyberone.com.au> <3F5AE7ED.7010501@cyberone.com.au> <3F5AF9D9.3070206@cyberone.com.au> In-Reply-To: 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 Content-Length: 1474 Lines: 43 John Yau wrote: >>Its actually more important when you have smaller timeslices, because >>the interactive task is more likely to use all of its timeslice in a >>burst of activity, then getting stuck behind all the cpu hogs. >> >> > >Well, I didn't claim it'd be optimal, I just said that it's not worth the >extra effort. The interactive task will still finish in O((interactive_time >/ timeslice) * #hogs + interative_time) ms. As long as the cpu time >interactive tasks require are very short, they still should finish within a >reasonable amount of time. > I have found it to be worth the extra effort in my patches, but maybe you have something different in mind. > >>Yes. Also, say 5 hogs running, an interactive task needs to do something >>taking 2ms. At a 2ms timeslice, it will take 2ms. At a 1ms timeslice it >>will take 6ms. >> >> > >That's assuming that the interactive task gets scheduled first. In the >worst case scenario where it gets scheduled last, at 2 ms, it takes 12 ms >and at 1 ms it also takes 12 ms. Not much difference there. > > No, not much difference. If the worst case scenario happens, it indicates you have quite a big problem (ie. an interactive task not allowed to preempt cpu hogs). - 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/