From owner-freebsd-hackers Wed Aug 22 13:50:51 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from smtp3.xs4all.nl (smtp3.xs4all.nl [194.109.127.132]) by hub.freebsd.org (Postfix) with ESMTP id 214B137B42C for ; Wed, 22 Aug 2001 13:50:27 -0700 (PDT) (envelope-from wkb@freebie.xs4all.nl) Received: from freebie.xs4all.nl (freebie.xs4all.nl [213.84.32.253]) by smtp3.xs4all.nl (8.9.3/8.9.3) with ESMTP id WAA00509; Wed, 22 Aug 2001 22:50:25 +0200 (CEST) Received: (from wkb@localhost) by freebie.xs4all.nl (8.11.4/8.11.4) id f7MKoPV33159; Wed, 22 Aug 2001 22:50:25 +0200 (CEST) (envelope-from wkb) Date: Wed, 22 Aug 2001 22:50:25 +0200 From: Wilko Bulte To: Thierry Herbelot Cc: hackers@FreeBSD.ORG Subject: Re: clock synchronization quality via NTP ? Message-ID: <20010822225025.A33131@freebie.xs4all.nl> References: <3B840C56.BDB7424D@herbelot.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <3B840C56.BDB7424D@herbelot.com>; from thierry@herbelot.com on Wed, Aug 22, 2001 at 09:47:34PM +0200 X-OS: FreeBSD 4.3-STABLE X-PGP: finger wilko@freebsd.org Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Wed, Aug 22, 2001 at 09:47:34PM +0200, Thierry Herbelot wrote: > Hello, > > I know FreeBSD can be used with great success for timing solutions (at > least two core members do it ?). > > has someone some performance data of the quality of system clock > synchronization, while using NTPd with a GPS reveiver and a hard 1PPS > signal ? > > More precisely : is it reasonable to hope having a system clock not > farther from the GPS clock by more than 50 micro-seconds ? Talk to Poul-Henning, he is the clock/time expert (phk@FreeBSD.org). Poul used to have some nice Web pages around on this subject but they were killed in a disk crash IIRC. -- | / o / / _ Arnhem, The Netherlands email: wilko@FreeBSD.org |/|/ / / /( (_) Bulte To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message