From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932339AbWCHCul (ORCPT ); Tue, 7 Mar 2006 21:50:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932349AbWCHCul (ORCPT ); Tue, 7 Mar 2006 21:50:41 -0500 Received: from ishtar.tlinx.org ([64.81.245.74]:10629 "EHLO ishtar.tlinx.org") by vger.kernel.org with ESMTP id S932339AbWCHCuk (ORCPT ); Tue, 7 Mar 2006 21:50:40 -0500 Message-ID: <440E467D.70804@tlinx.org> Date: Tue, 07 Mar 2006 18:50:37 -0800 From: Linda Walsh User-Agent: Thunderbird 1.5 (Windows/20051201) MIME-Version: 1.0 To: Jesper Juhl CC: Magnus Damm , Linux Kernel Mailing List Subject: FWIW: Re: SMP and 101% cpu max? References: <9a8748490603070507h48e2fe02qbf9da7956e794161@mail.gmail.com> In-Reply-To: <9a8748490603070507h48e2fe02qbf9da7956e794161@mail.gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org FYI, running/compiling 2.6.15.5 on a 2x(1GHzxP-III), 1GB times for "make" -jn bzImage (no modules): (using export TIMEFORMAT="%2Rsec %2Uusr %2Ssys (%P%% cpu)" ) -j1: 815.80sec 745.64usr 78.74sys (100.00% cpu) -j2: 445.17sec 778.68usr 86.22sys (100.00% cpu) -j3: 444.89sec 781.66usr 87.84sys (100.00% cpu) -j4: 443.08sec 781.81usr 87.97sys (100.00% cpu) -j5: 445.98sec 782.53usr 87.51sys (100.00% cpu) ----- I am not seeing the symptom you are describing. The load increases proportionately to the 'job limit', but it doesn't radically change the overall cpu required. As I have only 2 cpu's, I can't expect much benefit beyond 2x, with actual approaching closer to 1.8x. -l Jesper Juhl wrote: > On 3/7/06, Magnus Damm wrote: > >> With 128MB and 256MB configurations, a majority of the tests never >> make it over 101% CPU usage when I run "make -j 2 bzImage", building a >> allnoconfig kernel. With 64MB memory, everything seems to be working >> as expected. Also, running "make bzImage" works as expected too. >> > Hmm, I wonder if it's related to the problem I reported here : > http://lkml.org/lkml/2006/2/28/219 > Where I need to run make -j 5 or higher to load both cores of my Athlon X2. >