Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Tue, 16 Apr 2002 18:58:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Tue, 16 Apr 2002 18:58:47 -0400 Received: from h24-67-14-151.cg.shawcable.net ([24.67.14.151]:61683 "EHLO webber.adilger.int") by vger.kernel.org with ESMTP id ; Tue, 16 Apr 2002 18:58:43 -0400 From: Andreas Dilger Date: Tue, 16 Apr 2002 16:56:31 -0600 To: Herbert Xu Cc: linux-kernel@vger.kernel.org Subject: Re: Why HZ on i386 is 100 ? Message-ID: <20020416225631.GD20464@turbolinux.com> Mail-Followup-To: Herbert Xu , linux-kernel@vger.kernel.org In-Reply-To: <20020416222156.GB20464@turbolinux.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.27i X-GPG-Key: 1024D/0D35BED6 X-GPG-Fingerprint: 7A37 5D79 BF1B CECA D44F 8A29 A488 39F5 0D35 BED6 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Apr 17, 2002 08:37 +1000, Herbert Xu wrote: > Why are we still measuring uptime using the tick variable? Ticks != time. > Surely we should be recording the boot time somewhere (probably on a > file system), and then comparing that with the current time? Er, because the 'tick' is a valid count of the actual time that the system has been running, while the "boot time" is totally meaningless. What if the system has no RTC, or the RTC is wrong until later in the boot sequence when it can be set by the user/ntpd? What if you pass daylight savings time? Does your uptime increase/decrease by an hour? Cheers, Andreas -- Andreas Dilger http://www-mddsp.enel.ucalgary.ca/People/adilger/ http://sourceforge.net/projects/ext2resize/ - 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/