From owner-cvs-all Wed Apr 7 13:21:43 1999 Delivered-To: cvs-all@freebsd.org Received: from zibbi.mikom.csir.co.za (zibbi.mikom.csir.co.za [146.64.24.58]) by hub.freebsd.org (Postfix) with ESMTP id 5FE0C1589B; Wed, 7 Apr 1999 13:21:33 -0700 (PDT) (envelope-from jhay@zibbi.mikom.csir.co.za) Received: (from jhay@localhost) by zibbi.mikom.csir.co.za (8.9.3/8.9.3) id WAA11097; Wed, 7 Apr 1999 22:18:51 +0200 (SAT) (envelope-from jhay) From: John Hay Message-Id: <199904072018.WAA11097@zibbi.mikom.csir.co.za> Subject: Re: cvs commit: src/sys/kern kern_time.c In-Reply-To: <199904071924.MAA05436@apollo.backplane.com> from Matthew Dillon at "Apr 7, 1999 12:24:29 pm" To: dillon@apollo.backplane.com (Matthew Dillon) Date: Wed, 7 Apr 1999 22:18:51 +0200 (SAT) Cc: Don.Lewis@tsc.tdk.com, nsayer@FreeBSD.org, cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org X-Mailer: ELM [version 2.4ME+ PL43 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk > :On Apr 7, 9:36am, Nick Sayer wrote: > :} Subject: cvs commit: src/sys/kern kern_time.c > : > :} We still need to decide on an algorithm to clamp positive adjustments. > :} As it stands, it is possible to achieve arbitrary negative adjustments > :} by "wrapping" time around. > : > :Limit positive steps to MIN(1 second, elapsed time since last postive step). > :At worst the clock could be made to run at 2x normal speed. > : > : --- Truck > > That's a pretty good solution. If this is combined with calling > 'ntpdate' on boot to step the time prior to starting xntpd, I think > we wind up with quite a reasonable setup. Once stepped, xntpd isn't > likely to have to do anything major. Besides, in order to be 'safe' > from PC realtime clock chip Y2K issues you pretty much have to step > the time by syncing it to an external source with ntpdate on boot > anyway. > Well if this is just to keep (x)ntpd happy, you can just compile xntpd-3 with the SLEWALWAYS option or run ntpd-4 with the -x option and it shouldn't ever step the time... At least that is what the docs and source says. I haven't tried it myself. John -- John Hay -- John.Hay@mikom.csir.co.za To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message