Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!mp.cs.niu.edu!bennett
From: bennett@mp.cs.niu.edu (Scott Bennett)
Newsgroups: comp.os.mach
Subject: Re: Mach as a Virtual Machine
Keywords: Mach, Virtual Machine OS
Message-ID: <1991Apr18.205420.13525@mp.cs.niu.edu>
Date: 18 Apr 91 20:54:20 GMT
References: <(Pierre> <Mareschal)> <1991Apr17.043604.20010@cs.cmu.edu>
Organization: Northern Illinois University
Lines: 47

In article <1991Apr17.043604.20010@cs.cmu.edu> af@cs.cmu.edu (Alessandro Forin) writes:
>
>> I am trying to answer this question:
>> 			"Is Mach a virtual machine software?"
>  [text deleted  --SJB]
>	Execute programs intended for an Operating System under 
>	a different one
>	
>	Execute an entire Operating System on top of another
>	
>	Execute multiple Operating Systems on top of a single one
>
>	Execute programs intended for a variety of Operating System
>	under the same, different one
>	@end(Itemize)
>
>The IBM's approach covers all points, (4) being a consequence of (3).
>In Mach we capture esp (1) and (4), but in some cases [e.g. MS-DOS in
>virtual 86 mode] even (2).  I do not believe point (3) per-se is of much
>value, users just want to run their programs after all.  And the faster
>they run the happier they are.

     The above belief about the third goal is out of touch with
operational reality.  Most shops cannot dedicate an entire machine
to the purposes of installing, configuring, testing, and fixing new
versions of even the *same* operating system before putting them
into production use.  Having the ability to run multiple operating
systems (or multiple versions thereof) concurrently in the same box
is a real blessing to many shops and their budgets.
>
>  [more text deleted  --SJB]
>
>sandro-


                                  Scott Bennett, Comm. ASMELG, CFIAG
                                  Systems Programming
                                  Northern Illinois University
                                  DeKalb, Illinois 60115
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