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Path: utzoo!utgpu!water!watmath!clyde!rutgers!rochester!cornell!batcomputer!chow
From: chow@batcomputer.UUCP
Newsgroups: comp.sys.mac
Subject: Re: Virtual Memory with the Mac OS
Message-ID: <2542@batcomputer.tn.cornell.edu>
Date: Sat, 3-Oct-87 13:34:30 EDT
Article-I.D.: batcompu.2542
Posted: Sat Oct  3 13:34:30 1987
Date-Received: Sun, 4-Oct-87 02:35:24 EDT
References: <2653@okstate.UUCP>
Reply-To: chow@tcgould.tn.cornell.edu (Christopher Chow)
Organization: Cornell Theory Center, Cornell University, Ithaca NY
Lines: 21
Keywords: virtual memory 68851

In article <2653@okstate.UUCP> norman@a.cs.okstate.edu (Norman Graham) writes:
>Does anyone out there know what it would take to have demand paging virtual 
>memory on the Mac II?  Could it be as simple as plugging in a 68851 and 
>writing an interrupt handler to take care of swapping the pages?
>

One thing which you might want to question is whether if you want to add an
68851 MMU to your Mac II.  I'm not a hardware guru, but from what
understand, the 68851 chip adds wait state(s) to every memory reference.
How's that for slowing down your machine.  Note that Suns, etc., all use
their custom MMU chips to avoid the wait state problems with the Motorola
chip.

Christopher Chow
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