From owner-freebsd-hackers@FreeBSD.ORG Fri Jan 21 13:27:26 2005 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C635016A4CE for ; Fri, 21 Jan 2005 13:27:26 +0000 (GMT) Received: from mail26.sea5.speakeasy.net (mail26.sea5.speakeasy.net [69.17.117.28]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9663543D39 for ; Fri, 21 Jan 2005 13:27:26 +0000 (GMT) (envelope-from ayerkes@speakeasy.net) Received: (qmail 2572 invoked from network); 21 Jan 2005 13:27:26 -0000 Received: from dsl081-145-152.chi1.dsl.speakeasy.net (HELO firebird) ([64.81.145.152]) (envelope-sender ) by mail26.sea5.speakeasy.net (qmail-ldap-1.03) with SMTP for ; 21 Jan 2005 13:27:26 -0000 Date: Fri, 21 Jan 2005 08:00:53 -0600 From: art yerkes To: freebsd-hackers@freebsd.org Message-Id: <20050121080053.580f7181.ayerkes@speakeasy.net> In-Reply-To: <41F0EB25.5030404@spintech.ro> References: <20050120004406.GF921@einstein.lab> <41EFBEA5.50007@spintech.ro> <84dead72050120181965c70231@mail.gmail.com> <41F0EB25.5030404@spintech.ro> X-Mailer: Sylpheed version 0.9.10 (GTK+ 1.2.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: clock time in milliseconds into a c program X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 21 Jan 2005 13:27:26 -0000 Remember to calibrate RDTSC against the RTC first if you're using it in production. It's quite accurate but some mobile CPUs count in coarser units than you'd predict from master clock rate. -- Here's a simple experiment. Stand on a train track between two locomotives which are pushing on you with equal force in opposite directions. You will exhibit no net motion. None the less, you may soon begin to notice that something important is happening. -- Robert Stirniman