From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966082AbXDCBHp (ORCPT ); Mon, 2 Apr 2007 21:07:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S966138AbXDCBHp (ORCPT ); Mon, 2 Apr 2007 21:07:45 -0400 Received: from mail09.syd.optusnet.com.au ([211.29.132.190]:34185 "EHLO mail09.syd.optusnet.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966082AbXDCBHo (ORCPT ); Mon, 2 Apr 2007 21:07:44 -0400 From: Con Kolivas To: Ingo Molnar Subject: Re: [test] hackbench.c interactivity results: vanilla versus SD/RSDL Date: Tue, 3 Apr 2007 11:07:22 +1000 User-Agent: KMail/1.9.5 Cc: linux list , Andrew Morton , Mike Galbraith References: <20070329112249.GA32665@elte.hu> In-Reply-To: <20070329112249.GA32665@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200704031107.22642.kernel@kolivas.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thursday 29 March 2007 21:22, Ingo Molnar wrote: > [ A quick guess: could SD's substandard interactivity in this test be > due to the SMP migration logic inconsistencies Mike noticed? This is > an SMP system and the hackbench workload is very scheduling intense > and tasks are frequently queued from one CPU to another. ] I assume you put it on and endless loop since hackbench 10 runs for .5 second on my machine. Doubtful it's an SMP issue. update_if_moved should maintain cross cpu scheduling decisions. The same slowdown would happen on UP and is almost certainly due to the fact that hackbench 10 induces a load of _160_ on the machine. -- -ck