From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 14 Jan 2003 14:58:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 14 Jan 2003 14:58:22 -0500 Received: from zcars04f.nortelnetworks.com ([47.129.242.57]:34558 "EHLO zcars04f.nortelnetworks.com") by vger.kernel.org with ESMTP id ; Tue, 14 Jan 2003 14:58:21 -0500 Message-ID: <3E246DE5.7080302@nortelnetworks.com> Date: Tue, 14 Jan 2003 15:07:01 -0500 X-Sybari-Space: 00000000 00000000 00000000 From: Chris Friesen User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.8) Gecko/20020204 X-Accept-Language: en-us MIME-Version: 1.0 To: Maciej Soltysiak Cc: linux-kernel@vger.kernel.org Subject: Re: timing an application References: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Maciej Soltysiak wrote: > Hi, > > being inspired by some book about optimizing c++ code i decided to do > timing of functions i wrote. I am using gettimeofday to set > two timeval structs and calculate the time between them. > But the results depend heavily on the load, also i reckon that this > is an innacurate timing. > > Any ideas on timing a function, or a block of code? Maybe some kernel > timers or something. gettimeofday() is accurate. However, your task may be interrupted by other tasks, interrupts, etc. Your best bet may be to do many iterations of the routine in question and then do some statistical analysis of the results. Chris -- Chris Friesen | MailStop: 043/33/F10 Nortel Networks | work: (613) 765-0557 3500 Carling Avenue | fax: (613) 765-2986 Nepean, ON K2H 8E9 Canada | email: cfriesen@nortelnetworks.com