Subject: Re: date and time
To: Todd Whitesel <toddpw@best.com>
From: Miles Nordin <carton@Ivy.NET>
List: port-mac68k
Date: 02/01/2000 23:11:24
On Tue, 1 Feb 2000, Todd Whitesel wrote:

> Why hasn't someone hacked up something that reads the battery clock every
> hour and syncs the Unix clock to it?

If it were done just that crudely, the clock would ``skip.'' Perhaps it
was/is/should-be thought that losing the ability to semi-accurately time
_intervals_ of wall-time leads to greater insanity than the relatively
well-understood situation of having the wrong time.  That's not
insolvable--one could for example have xntp sync to the hardware clock as
if it were a reference clock.  But, kludging it properly is perhaps
complicated enough that the lack of solution isn't embarrassing. :)

I think I heard on the list some people have trouble even with xntp
because there is too much jitter or something.  It might help such a
person to change /sys/sys/timex.h on this line:

#define MAXFREQ (512L << SHIFT_USEC)

to something absurdly huge.  1024 was enough to make my alpha Avanti sync
with xntp, but if that's not good enough why stop there?  It's not the
same as having a clock that works, but maybe it's better than nothing.

-- 
Miles Nordin / v:+1 720 841-8308 fax:+1 530 579-8680
555 Bryant Street PMB 182 / Palo Alto, CA 94301-1700 / US