Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 22 Nov 2002 00:34:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 22 Nov 2002 00:34:24 -0500 Received: from rwcrmhc53.attbi.com ([204.127.198.39]:59589 "EHLO rwcrmhc53.attbi.com") by vger.kernel.org with ESMTP id ; Fri, 22 Nov 2002 00:34:23 -0500 Message-ID: <3DDDC37F.5AC219D5@attbi.com> Date: Fri, 22 Nov 2002 00:41:19 -0500 From: Jim Houston Reply-To: jim.houston@attbi.com X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.4.17 i686) X-Accept-Language: en MIME-Version: 1.0 To: efault@gmx.de, linux-kernel@vger.kernel.org CC: riel@conectiva.com.br Subject: Re: 2.5.47 scheduler problems? Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1104 Lines: 29 Hi Mike, Rik, Everyone, The O(1) schedule just isn't fair. It will run a subset of the runable processes excluding the rest. See my earlier emails for the details. I had been working on a fix for this but got distracted by Posix timers. I still hope to get back to it. My patch is here: http://marc.theaimsgroup.com/?l=linux-kernel&m=103508412423719&w=2 It fixes fairness but breaks nice(2). Rik van Riel has a patch here which builds on my patch which fixes this: http://marc.theaimsgroup.com/?l=linux-kernel&m=103651801424031&w=2 I just gave this a spin with. The patches still apply cleanly to linux-2.5.48 and it seems well behaved:-) I found this problem with the LTP waitpid06 test. It actually produced a live-lock. See this mail: http://marc.theaimsgroup.com/?l=linux-kernel&m=103133744217082&w=2 Jim Houston - Concurrent Computer Corp. - 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/