From owner-freebsd-hackers Sun Mar 31 12:35:14 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from rover.village.org (rover.bsdimp.com [204.144.255.66]) by hub.freebsd.org (Postfix) with ESMTP id 35FA737B41D for ; Sun, 31 Mar 2002 12:34:52 -0800 (PST) Received: from harmony.village.org (harmony.village.org [10.0.0.6]) by rover.village.org (8.11.3/8.11.3) with ESMTP id g2VKYoi46455; Sun, 31 Mar 2002 13:34:51 -0700 (MST) (envelope-from imp@village.org) Received: from localhost (warner@rover2.village.org [10.0.0.1]) by harmony.village.org (8.11.6/8.11.6) with ESMTP id g2VKYmf51597; Sun, 31 Mar 2002 13:34:48 -0700 (MST) (envelope-from imp@village.org) Date: Sun, 31 Mar 2002 13:34:02 -0700 (MST) Message-Id: <20020331.133402.125794917.imp@village.org> To: dp@penix.org Cc: silby@silby.com, bicknell@ufp.org, hackers@FreeBSD.ORG Subject: Re: GPS time. From: "M. Warner Losh" In-Reply-To: References: <20020331091304.U40871-100000@patrocles.silby.com> X-Mailer: Mew version 2.1 on Emacs 21.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit 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 In message: Paul Halliday writes: : This is the answer I was kinda hoping for. I think that accuracy : to ~100ms from a known source is a little more comforting than <1ms from a : server that I have no control over. I am not maintaining a space program, : just a dozen machines in my room that really serve no other purpose than : personal entertainment. Also keep in mind that the US governement reserves the right to turn off GPS at any time to selected regions of the globe. The problem with the large variation in time is that if you are trying to use it for a NTP reference clock, bad things happen to the algorythm and you get substantially worse performance than you would otherwise. Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message