Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750711AbVJNKVE (ORCPT ); Fri, 14 Oct 2005 06:21:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750709AbVJNKVE (ORCPT ); Fri, 14 Oct 2005 06:21:04 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:36535 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S1750712AbVJNKVB (ORCPT ); Fri, 14 Oct 2005 06:21:01 -0400 Subject: Re: [patch] optimize disk_round_stats From: Arjan van de Ven To: "Chen, Kenneth W" Cc: linux-kernel@vger.kernel.org, "'Jens Axboe'" In-Reply-To: <200510131919.j9DJJkg07781@unix-os.sc.intel.com> References: <200510131919.j9DJJkg07781@unix-os.sc.intel.com> Content-Type: text/plain Date: Fri, 14 Oct 2005 12:19:46 +0200 Message-Id: <1129285187.2873.7.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-Spam-Score: 2.9 (++) X-Spam-Report: SpamAssassin version 3.0.4 on pentafluge.infradead.org summary: Content analysis details: (2.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.1 RCVD_IN_SORBS_DUL RBL: SORBS: sent directly from dynamic IP address [80.57.133.107 listed in dnsbl.sorbs.net] 2.8 RCVD_IN_DSBL RBL: Received via a relay in list.dsbl.org [] X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 589 Lines: 13 On Thu, 2005-10-13 at 12:19 -0700, Chen, Kenneth W wrote: > Following the same idea, it occurs to me that we should only update > disk stat when "now" is different from disk->stamp. Otherwise, we > are again needlessly adding zero to the stats. have you measured this? Conditionals in code are not free, so it might well be more expensive... - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/