Subject: Re: Clock slowdown
To: Scott Frederick Kaplan <sfkaplan@cs.utexas.edu>
From: Allen Briggs <briggs@puma.bevd.blacksburg.va.us>
List: port-mac68k
Date: 09/21/1995 14:23:08
> Here's a new one, and if it's a known problem I apologize--I did my
> best to hunt through FAQ's and the web pages to see if I could find an
> answer to this one.  My clock slows down.  To be more specfic:

It is a known, but not often asked about problem.  It's root is in the
fact that the clock interrupts are at the lowest interrupt priority
level on the mac...  When you do much of anything, it loses clock ticks
(each one is 1/60 seconds) interrupts.  I can give a more detailed
description if anyone requires it.

The clock will drift the most with heavy SCSI, serial, or ethernet
access.  This is a little better with the SCSI driver that I'm working
on (just because the driver is faster and moves smaller chunks of data).

There are some ways to kludge this, I think.  It's not a large priority
for me as I have a cron job resetting my date every 15 min. (or so ;-)
from a time server.

-allen

-- 
Allen Briggs - end killing - allen.briggs@bev.net ** MacBSD == NetBSD/mac68k **
   Where does all my time go?  <a href="http://www.netbsd.org/">Guess.</a>