From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753355Ab1EDLOG (ORCPT ); Wed, 4 May 2011 07:14:06 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:45666 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752818Ab1EDLOE (ORCPT ); Wed, 4 May 2011 07:14:04 -0400 Date: Wed, 4 May 2011 13:13:55 +0200 From: Ingo Molnar To: Nikhil Rao Cc: Peter Zijlstra , Mike Galbraith , linux-kernel@vger.kernel.org, "Nikunj A. Dadhania" , Srivatsa Vaddagiri , Stephan Barwolf Subject: Re: [PATCH v1 00/19] Increase resolution of load weights Message-ID: <20110504111355.GC5914@elte.hu> References: <1304299157-25769-1-git-send-email-ncrao@google.com> <20110502061411.GA16682@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Nikhil Rao wrote: > Also, out of curiosity, what's an acceptable tolerance level for a > performance hit on 32-bit? It's a cost/benefit analysis and for 32-bit systems the benefits seem to be rather small, right? Can we make the increase in resolution dependent on max CPU count or such and use cheaper divides on 32-bit in that case, while still keeping the code clean? We'd expect only relatively large and new (and 64-bit) systems to run into resolution problems, right? Thanks, Ingo