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From: Mike Meyer <mwm@mired.org>
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Date: Thu, 16 Aug 2001 09:25:07 -0500
To: "P. U. (Uli) Kruppa" <root@pukruppa.de>
Cc: questions@freebsd.org
Subject: Re: Multi-CPU system [was:Re: your mail]
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P. U. (Uli) Kruppa <root@pukruppa.de> types:
> Of course this is completely off-topic and I am a complete
> ignorant but
> could one run two OS's at the same time on a dual-CPU
> machine?

You don't even need multiple CPUs; you just need the right
architecture.  According to what Andrew said about the IA
architecture, it isn't one of those.

IBM's VM architecture allowed you to run multiple OS's on one machine,
so well that one sysadmin installed VM without telling his bosses, and
got away with running MVS under VM for months before anyone caught on.
The latest version of this technology can be seen at <URL:
http://www-1.ibm.com/servers/eserver/zseries/os/ >, which lets you run
linux systems at around US$.50 each.

Multics would run different versions on different CPUs. You could do
an OS upgrade without downtime by upgrading each CPU in turn.

	<mike
--
Mike Meyer <mwm@mired.org>			http://www.mired.org/home/mwm/
Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information.

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