From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030829AbWKOSdQ (ORCPT ); Wed, 15 Nov 2006 13:33:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030830AbWKOSdQ (ORCPT ); Wed, 15 Nov 2006 13:33:16 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:56284 "EHLO mx2.mail.elte.hu") by vger.kernel.org with ESMTP id S1030829AbWKOSdO (ORCPT ); Wed, 15 Nov 2006 13:33:14 -0500 Date: Wed, 15 Nov 2006 19:31:52 +0100 From: Ingo Molnar To: Jeremy Fitzhardinge Cc: Eric Dumazet , Andi Kleen , akpm@osdl.org, Arjan van de Ven , linux-kernel@vger.kernel.org Subject: Re: [PATCH] i386-pda UP optimization Message-ID: <20061115183152.GA3160@elte.hu> References: <1158046540.2992.5.camel@laptopd505.fenrus.org> <20061115173252.GA24062@elte.hu> <455B557C.7020602@goop.org> <200611151905.04712.dada1@cosmosbay.com> <455B5C54.1050301@goop.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <455B5C54.1050301@goop.org> User-Agent: Mutt/1.4.2.2i X-ELTE-SpamScore: -4.4 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-4.4 required=5.9 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=no SpamAssassin version=3.0.3 -3.3 ALL_TRUSTED Did not pass through any untrusted hosts -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0005] 1.5 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Jeremy Fitzhardinge wrote: > [...] However, when I measured segment register use timings, I didn't > see any dramatic costs associated with segment register use which > would account for a 5% hit in your benchmark. if by that measurement you mean time-segops.c, i dont think it correctly measures 'mixed' use of different selector values for the same %gs segment selector. And that's what i suggested for you to measure in September, and that's what Eric's testcase triggers too. Ingo