From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265367AbUBFKe4 (ORCPT ); Fri, 6 Feb 2004 05:34:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S265374AbUBFKe4 (ORCPT ); Fri, 6 Feb 2004 05:34:56 -0500 Received: from dp.samba.org ([66.70.73.150]:33435 "EHLO lists.samba.org") by vger.kernel.org with ESMTP id S265367AbUBFKez (ORCPT ); Fri, 6 Feb 2004 05:34:55 -0500 Date: Fri, 6 Feb 2004 21:30:10 +1100 From: Anton Blanchard To: Rick Lindsley Cc: piggin@cyberone.com.au, akpm@osdl.org, linux-kernel@vger.kernel.org, mjbligh@us.ibm.com, dvhltc@us.ibm.com Subject: Re: [PATCH] Load balancing problem in 2.6.2-mm1 Message-ID: <20040206103010.GI19011@krispykreme> References: <200402060924.i169OWx30517@owlet.beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200402060924.i169OWx30517@owlet.beaverton.ibm.com> User-Agent: Mutt/1.5.5.1+cvs20040105i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, > This patch allows for this_load to set max_load, which if I understand > the logic properly is correct. It then adds a check to imbalance to make > sure a negative number hasn't been coerced into a large positive number. > With this patch applied, the algorithm is *much* more conservative ... > maybe *too* conservative but that's for another round of testing ... Good stuff, I just gave the patch a spin and things seem a little calmer. However Im still seeing a lot of balancing going on within a node. Setup: 2 threads per cpu. 2 nodes of 16 threads each. I ran a single "yes > /dev/null" And it looks like that process is bouncing around the entire node. Below is a 2 second average. Anton cpu user system idle cpu user system idle node 0: cpu0 2 0 99 cpu1 9 0 91 cpu2 1 0 99 cpu3 8 0 92 cpu4 3 0 97 cpu5 10 0 90 cpu6 2 0 98 cpu7 10 0 90 cpu8 2 0 98 cpu9 9 0 90 cpu10 3 0 96 cpu11 9 0 90 cpu12 2 0 98 cpu13 10 0 90 cpu14 2 1 97 cpu15 10 1 89 node 1: cpu16 0 0 100 cpu17 0 0 100 cpu18 0 0 101 cpu19 0 0 100 cpu20 0 0 100 cpu21 0 0 101 cpu22 0 0 101 cpu23 0 0 100 cpu24 0 0 100 cpu25 0 0 100 cpu26 0 0 100 cpu27 0 0 100 cpu28 0 0 101 cpu29 0 0 100 cpu30 0 0 100 cpu31 0 0 100