Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756170AbYJWMia (ORCPT ); Thu, 23 Oct 2008 08:38:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752495AbYJWMiW (ORCPT ); Thu, 23 Oct 2008 08:38:22 -0400 Received: from welcomes-you.com ([85.214.50.128]:39966 "EHLO smtp.welcomes-you.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752050AbYJWMiV (ORCPT ); Thu, 23 Oct 2008 08:38:21 -0400 X-Greylist: delayed 1542 seconds by postgrey-1.27 at vger.kernel.org; Thu, 23 Oct 2008 08:38:21 EDT Message-ID: <49006A30.7030208@aei.mpg.de> Date: Thu, 23 Oct 2008 14:12:32 +0200 From: Carsten Aulbert User-Agent: Thunderbird 2.0.0.17 (X11/20080925) MIME-Version: 1.0 To: linux-kernel@vger.kernel.org CC: Henning Fehrmann Subject: Idle core on overloaded CPU? X-Enigmail-Version: 0.95.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 906 Lines: 27 Hi, on Intel X3220 CPU based systems (4 physical cores) I came across the following thing (Debian etch, with vanilla kernel 2.6.25.9): starting the following: $ screen -d -m stress -c 2 $ nice -19 screen -d -m stress -c 4 This causes two cores to be 100% busy in user state and one core to be busy in 100% nice state. However, the remaining core is idle. Even watching it over longer stretches of time, the situation remains static. I guess it's a kernel misconfiguration on my part (config available here: https://n0.aei.uni-hannover.de/linux/kernel/config-2.6.25.9-nodes ), but if not could this be a scheduling bug? Thanks for any hint Cheers Carsten -- 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/