From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965606AbXDVJy2 (ORCPT ); Sun, 22 Apr 2007 05:54:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030181AbXDVJy1 (ORCPT ); Sun, 22 Apr 2007 05:54:27 -0400 Received: from mail19.syd.optusnet.com.au ([211.29.132.200]:45426 "EHLO mail19.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965606AbXDVJy1 (ORCPT ); Sun, 22 Apr 2007 05:54:27 -0400 From: Con Kolivas To: Willy Tarreau Subject: Re: [ANNOUNCE] Staircase Deadline cpu scheduler version 0.45 Date: Sun, 22 Apr 2007 19:53:24 +1000 User-Agent: KMail/1.9.5 Cc: linux kernel mailing list , ck list , Ingo Molnar , Mike Galbraith , Al Boldi , Peter Williams , Nick Piggin , Matt Mackall , Bill Huey , William Lee Irwin III , Gene Heskett References: <200704221441.48897.kernel@kolivas.org> <200704221853.59358.kernel@kolivas.org> <20070422091451.GA15913@1wt.eu> In-Reply-To: <20070422091451.GA15913@1wt.eu> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200704221953.25157.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sunday 22 April 2007 19:14, Willy Tarreau wrote: > On Sun, Apr 22, 2007 at 06:53:58PM +1000, Con Kolivas wrote: > > On Sunday 22 April 2007 18:06, Willy Tarreau wrote: > > > On Sun, Apr 22, 2007 at 05:31:58PM +1000, Con Kolivas wrote: > > > > On Sunday 22 April 2007 17:27, Con Kolivas wrote: > > > > > On Sunday 22 April 2007 17:00, Willy Tarreau wrote: > > > > > > On Sun, Apr 22, 2007 at 02:41:48PM +1000, Con Kolivas wrote: > > > > > > > A significant bugfix for SMP balancing was just posted for the > > > > > > > staircase deadline cpu scheduler which improves behaviour > > > > > > > dramatically on any SMP machine. > > > > > > > > > > > > > > Thanks to Willy Tarreau for noticing likely fault point. > > > > > > > > > > > > > > Also requested was a version in the Makefile so this version of > > > > > > > the patch adds -sd045 to the kernel version. > > > > > > > > > > > > Con, I'm sorry, but it is worse with this one :-( > > > > > > > > > > Well that was quick testing, thanks. > > > > > > > > > > > The lag when typing in xterms is even more noticeable and vmstat > > > > > > output oscillates between 8 and 65, with idle rates around 50%, > > > > > > as you can see below : > > > > > > > > > > > > Renicing X or not does not change anything here. > > > > > > > > > > > > I suspect that the bug you fixed was hiding another one :-/ > > > > > > If you want me to test another patch, feel free to ask. > > > > > > > > Just as a debug point could you please try this patch? Thanks. > > > > > > OK, this time, the ocbench took ages to start. They appeared > > > immediately but very few of them (less than 8 out of 64) really started > > > to work. The system remained very responsive and smooth during the > > > test. But I guess I know why : all the load was sent to CPU 0 : > > > > Shouldn't have affected smp balancing at all, but try this on top of the > > ontop please? Thanks > > Does not change anything. There clearly is a huge regression somewhere :-/ > The second CPU is not used by ocbench, and again, out of 64 tasks, only > a small bunch (between 4 and 8) do something. > > Con, you should review the changes between 0.44 and 0.45, I think you > introduced a bug which broke fairness while fixing another one. Hmm; well it was "better" without the first debug patch I sent (even though it ws worse than 0.44) which is important in itself. I thank you greatly for your testing so far. Unfortunately I'm close to a one man code show so I'll have to spend time reviewing it further. The changes so far look ok still. Something else is lurking. Thanks! -- -ck