Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!cs.utexas.edu!rutgers!cmcl2!yale!jellinghaus-robert
From: jellinghaus-robert@CS.YALE.EDU (Rob Jellinghaus)
Newsgroups: comp.sys.mac
Subject: Re: When will MacOS get virtual memory?
Summary: NOT.
Message-ID: <39513@yale-celray.yale.UUCP>
Date: 4 Oct 88 18:11:52 GMT
References: <5624@zodiac.UUCP> <76000290@p.cs.uiuc.edu>
Sender: root@yale.UUCP
Reply-To: jellinghaus-robert@yale.UUCP
Organization: Yale University Computer Science Dept, New Haven CT  06520-2158
Lines: 30

In article <76000290@p.cs.uiuc.edu> gillies@p.cs.uiuc.edu writes:
>The sad thing is, the vast majority of Macintoshes in this world
>cannot support virtual memory.  This is because the 68000 chip has a
>design flaw that doesn't allow virtual memory to be implemented.

Someone really should tell Sun or Apollo.  They've produced many workstations
with 68000's running UNIX, which DOES support virtual memory and page swapping.
Gosh, wonder how they do it?

>I guess if Apple really intended to support virtual memory soon in all
>macintoshes, then it would have put a 68020 or at least a 68010 in the
>Mac SE.  But since most machines (SE's, Plus's) have the 68000, these
>machines will not have virtual memory any time soon.

Virtual memory doesn't REQUIRE hardware memory management.  It's a lot easier
if you have the PMMU, but it's not impossible to do on a 68000.  Apple, though,
probably won't bother to write its new OS for anything less than a 68020/68851
combo... gotta keep pushing into the future, ya know!

>Don Gillies, Dept. of Computer Science, University of Illinois
>1304 W. Springfield, Urbana, Ill 61801
>ARPA: gillies@cs.uiuc.edu   UUCP: {uunet,ihnp4,harvard}!uiucdcs!gillies

(Sanity check... this guy's in the CS dept.  He may be a professor.  And I'm
just a lowly undergrad... did I just shoot my mouth off?)

Rob Jellinghaus                | "SINGAPORE?!?  You're supposed to be a
jellinghaus-robert@CS.Yale.EDU |  COWBOY!  What kind of cowboy song is
ROBERTJ@{yalecs,yalevm}.BITNET |  THAT??!!  Singapore, I oughta--"
{everyone}!decvax!yale!robertj |      -- Eddie Foy, _The Cowboy Wally Story_