From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751371AbWDKRFJ (ORCPT ); Tue, 11 Apr 2006 13:05:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751378AbWDKRFJ (ORCPT ); Tue, 11 Apr 2006 13:05:09 -0400 Received: from [212.33.166.178] ([212.33.166.178]:3589 "EHLO raad.intranet") by vger.kernel.org with ESMTP id S1751371AbWDKRFH (ORCPT ); Tue, 11 Apr 2006 13:05:07 -0400 From: Al Boldi To: Con Kolivas Subject: Re: Fwd: Re: [patch][rfc] quell interactive feeding frenzy Date: Tue, 11 Apr 2006 20:03:24 +0300 User-Agent: KMail/1.5 References: <200604112100.28725.kernel@kolivas.org> In-Reply-To: <200604112100.28725.kernel@kolivas.org> Cc: linux-kernel@vger.kernel.org, Mike Galbraith MIME-Version: 1.0 Content-Type: text/plain; charset="windows-1256" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200604112003.24517.a1426z@gawab.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Con Kolivas wrote: > Hi Al Hi Con! > On Tuesday 11 April 2006 00:43, Al Boldi wrote: > > After that the loadavg starts to wrap. > > And even then it is possible to login. > > And that's not with the default 2.6 scheduler, but rather w/ spa. > > Since you seem to use plugsched, I wonder if you could tell me how does > current staircase perform with a load like that? With plugsched-2.6.16 your staircase sched reaches about 40 then slows down, maxing around 100. Setting sched_compute=1 causes console lock-ups. With staircase14.2-test3 it reaches around 300 then slows down, halting at around 500. Your scheduler seems to be tuned for single-user multi-tasking, i.e. concurrent tasks around 10, where its aggressive nature is sustained by a short run-queue. Once you go above 50, this aggressiveness starts to express itself as very jumpy. This is of course very cpu/mem/ctxt dependent and it would be great, if your scheduler could maybe do some simple on-the-fly benchmarking as it reschedules, thus adjusting this aggressiveness depending on its sustainability. Thanks! -- Al