From owner-freebsd-hackers Mon Sep 18 05:37:10 1995 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.6.12/8.6.6) id FAA14307 for hackers-outgoing; Mon, 18 Sep 1995 05:37:10 -0700 Received: from critter.tfs.com ([140.145.230.252]) by freefall.freebsd.org (8.6.12/8.6.6) with ESMTP id FAA14301 for ; Mon, 18 Sep 1995 05:37:07 -0700 Received: from localhost (localhost [127.0.0.1]) by critter.tfs.com (8.6.11/8.6.9) with SMTP id FAA06601; Mon, 18 Sep 1995 05:35:46 -0700 X-Authentication-Warning: critter.tfs.com: Host localhost didn't use HELO protocol To: Bruce Evans cc: freebsd-hackers@FreeBSD.org, mal@aristotle.algonet.se Subject: Re: xntpd (or kernel) timekeeping problem? In-reply-to: Your message of "Mon, 18 Sep 1995 22:10:26 +1000." <199509181210.WAA23027@godzilla.zeta.org.au> Date: Mon, 18 Sep 1995 05:35:45 -0700 Message-ID: <6599.811427745@critter.tfs.com> From: Poul-Henning Kamp Sender: owner-hackers@FreeBSD.org Precedence: bulk > 11932 on your machine). Calibration is hard to do since there is no > generally available accurate clock. ISA systems have another clock (the > RTC) of unknown accuracy. On my machines it seems to be more accurate > and just as stable as the 8254 clock. Actually I used xntpd to calibrate, I ran it, figured out that the drift was terrible/untolerable, tweaked the kernel, waited a week, tweaked it some more, waited a week, until my ntp had a nice avg drift of almost zero over a week... (notice that ntp may itself have a diurnal (or other period) variance depending on your networks load, but over a week, you will get the drift (pun intended) :-) What we really need is a neat little utility you can run by hand, that will run a ntpdate and figure out your drift since last you did that... -- Poul-Henning Kamp | phk@FreeBSD.ORG FreeBSD Core-team. http://www.freebsd.org/~phk | phk@login.dknet.dk Private mailbox. whois: [PHK] | phk@ref.tfs.com TRW Financial Systems, Inc. Just that: dried leaves in boiling water ?