From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751184AbWIHUTp (ORCPT ); Fri, 8 Sep 2006 16:19:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751199AbWIHUTp (ORCPT ); Fri, 8 Sep 2006 16:19:45 -0400 Received: from omx2-ext.sgi.com ([192.48.171.19]:20119 "EHLO omx2.sgi.com") by vger.kernel.org with ESMTP id S1751184AbWIHUTo (ORCPT ); Fri, 8 Sep 2006 16:19:44 -0400 Date: Fri, 8 Sep 2006 13:19:28 -0700 (PDT) From: Christoph Lameter To: "Siddha, Suresh B" cc: akpm@osdl.org, linux-kernel@vger.kernel.org, npiggin@suse.de, mingo@elte.hu Subject: Re: [PATCH] Fix longstanding load balancing bug in the scheduler. In-Reply-To: <20060908130028.A9446@unix-os.sc.intel.com> Message-ID: References: <20060908103529.A9121@unix-os.sc.intel.com> <20060908130028.A9446@unix-os.sc.intel.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 8 Sep 2006, Siddha, Suresh B wrote: > On Fri, Sep 08, 2006 at 11:40:51AM -0700, Christoph Lameter wrote: > > The balancing operation is not that frequent and having to treat a special > > case in the callers would make code more complicated and likely offset the > > gains in this function. > > This solution as such is not accurate and clean :) and my suggestion is > not making it any more ugly. > > With increase in NR_CPUS, cost of cpumask operations will increase and > we shouldn't penalize the other logical threads or cores sharing the caches by > bringing in unnecessary cache lines. One cacheline sized 128bytes will support all 1024 cpus that IA64 allows. cacheline align the cpumask?