From owner-freebsd-questions@FreeBSD.ORG Wed Mar 22 13:22:43 2006 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id C5C6616A401 for ; Wed, 22 Mar 2006 13:22:43 +0000 (UTC) (envelope-from wmoran@collaborativefusion.com) Received: from mx00.pub.collaborativefusion.com (mx00.pub.collaborativefusion.com [206.210.89.199]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9C2AD43D5E for ; Wed, 22 Mar 2006 13:22:36 +0000 (GMT) (envelope-from wmoran@collaborativefusion.com) Received: from vanquish.pgh.priv.collaborativefusion.com (vanquish.pgh.priv.collaborativefusion.com [192.168.2.61]) by wingspan with esmtp; Wed, 22 Mar 2006 08:22:35 -0500 id 00056441.44214F9B.000079CF Date: Wed, 22 Mar 2006 08:22:35 -0500 From: Bill Moran To: alfred.morgan@experclick.com Message-Id: <20060322082235.c5d62721.wmoran@collaborativefusion.com> In-Reply-To: <7c61221qt0meet1dudmids5vgcisejjjth@4ax.com> References: <44204E79.4090408@experclick.com> <7c61221qt0meet1dudmids5vgcisejjjth@4ax.com> Organization: Collaborative Fusion X-Mailer: Sylpheed version 2.2.0 (GTK+ 2.8.12; i386-portbld-freebsd6.0) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: freebsd-questions@freebsd.org Subject: Re: clock drifts after upgrade from 5.x to 6.x X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 22 Mar 2006 13:22:43 -0000 On Wed, 22 Mar 2006 00:46:57 +0000 John Murphy wrote: > Alfred Morgan wrote: > > > > > I have upgraded 4 different machines from various FreeBSD versions of > > 5 to various versions of 6 and 3 of the machines has a problem where > > the clock will drift very quickly slowing about 2 seconds per minute. > > Interesting. Were all the upgrades from versions less than 5.3 > I wonder? Reason I ask is that many people (including me) seem to > have started having problems with ntp around that time. There was > a thread in the stable mailing list about it here: > http://docs.freebsd.org/cgi/mid.cgi?20050401104508.GJ71384 Most machines these days have a number of clocks available. ACPI is likely choosing a less accurate clock than you would like. Apparently, with ACPI disabled, the default clock is pretty accurate. The worst examples of this are when you get calcru() errors because the clock actually appears to tick backwards sometimes. You can manually tell FreeBSD which clock to use via sysctl. I don't remember the magic incanation, but a few google searches should set you on the right path. Search for timecounter and calcru in addition to other terms relevent to your issue. -- Bill Moran Collaborative Fusion Inc.