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Date: Sat, 6 Apr 1996 00:40:48 -0600
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From: Tony Kimball <alk@Think.COM>
To: hackers@freebsd.org
Subject: Re: interrupts and such
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   From: Nate Williams <nate@sri.MT.net>
   Date: Fri, 5 Apr 1996 11:09:59 -0700

   > This seems excessive ...
   > So what is rtc0 and why is it acting like a clock interrupt?

   Because it is a clock interrupt.  rtc0 is 'sufficiently' faster than
   clk0 so that statistics gathering is significantly better and more
   accurate.  

This does not answer the question, however; it merely mutates it:
Why retain clk0?  It *does* seem a bit excessive.