From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265712AbTL3JnG (ORCPT ); Tue, 30 Dec 2003 04:43:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265713AbTL3JnF (ORCPT ); Tue, 30 Dec 2003 04:43:05 -0500 Received: from bay2-f70.bay2.hotmail.com ([65.54.247.70]:4363 "EHLO hotmail.com") by vger.kernel.org with ESMTP id S265712AbTL3Jmu (ORCPT ); Tue, 30 Dec 2003 04:42:50 -0500 X-Originating-IP: [193.172.9.1] X-Originating-Email: [aka_mr_zapper@hotmail.com] From: "g-j v dijk" To: roger.larsson@norran.net, linux-kernel@vger.kernel.org Subject: Re: Problem with SCHED_RR and kernel 2.4.18-4GB Date: Tue, 30 Dec 2003 10:42:48 +0100 Mime-Version: 1.0 Content-Type: text/plain; format=flowed Message-ID: X-OriginalArrivalTime: 30 Dec 2003 09:42:49.0127 (UTC) FILETIME=[4957D370:01C3CEB9] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > > The problem is that if I implement this, and set scheduling to be >SCHED_RR, > > or SCHED_FIFO, my linux machine hangs. With SCHED_OTHER, I don't have >that > > (note that for testing I used to set all prios to minimum (=1)). > >The big difference is that if a tread running as SCHED_RR or SCHED_FIFO >never >sleeps normal treads (like X, sh, login, ...) will not be given ANY CPU >time >- computer will appear hanged. Yep, I checked all threads. Not all threads have sleeps, but they do use semaphores or some blocking OS calls. Are you saying that's not enough? I think it should be, else the threads have design flaws. >[BTW you are not running the same code in both cases due to ifdefs...] Yep, IMHO you don't have to set the schedule type in "OTHER" mode. >But it is possible to get out of this situation if you prepared for it >before... Use a higher priority monitor to detect looping RT processes and >reduce their priorities! I like that Idea, it would be really appreciated if you could give me some sample code, just to get me started. Thanks a lot, Gert-Jan _________________________________________________________________ MSN Search, for accurate results! http://search.msn.nl