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From: Rick Kelly <rmk@toad.rmkhome.com>
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To: Johnny Billquist <bqt@update.uu.se>
Date: Tue, 13 Jun 2006 06:23:46 -0600 (MDT)
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Cc: John Nemeth <jnemeth@victoria.tc.ca>, misc@openbsd.org,
	Otto Moerbeek <otto@drijf.net>, Ted Unangst <ted.unangst@gmail.com>,
	Ted Mittelstaedt <tedm@toybox.placo.com>,
	Marcus Watts <mdw@umich.edu>, freebsd-questions@freebsd.org,
	=?ISO-8859-1?Q?H=E1morszky_Bal=E1zs?= <balihb@ogyi.hu>,
	netbsd-users@NetBSD.org, Nikolas Britton <nikolas.britton@gmail.com>
Subject: Re: wikipedia article
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Johnny Billquist said:

>> There's actually a cheesy way to do demand paging with microprocessors
>> that don't support demand paging (such as the original 68000--another
>> "16 bit" machine).  The way to do this is to run two processors in parallel
>> but skewed by one instruction.  If the first one does a bad memory fetch,
>> then the second one will not have fetched the instruction causing the
>> fault so contains restartable machine state.  Masscomp sold a machine
>> like this once.

>Didn't the first Apollos do this?

And also the Sun 1.

-- 
Rick Kelly	rmk@rmkhome.com
		<http://www.rmkhome.com/>
		<http://rkba.rmkhome.com/>