In article <n2vpmmF46gsU1@mid.individual.net>,
Ted Nolan <tednolan> <tednolan> wrote:

In article <10qe90l$kv9$2@gal.iecc.com>, John Levine <johnl@taugh.com> wrote: >>According to Peter Flass <Peter@Iron-Spring.com>:

The difference here is clear. My question is, what's the difference >>>between emulation and simulation? Is there a difference, even if only in >>>connotation. I'm never quite clear on whether to call something an >>>emulator or a simulator.

The usual rule of thumb is that emulation involves hardware or microcode >>support,
simulation is just software.

Virtualization is something else, where the architecture of the internal system
is the same as the external system so you can run the same operating system in
a virtual machine you can on the hardware, give or take very small tweaks.

I would say that's not quite complete, as you had the 386 being able to >virtualize the 8086, but not itself.

Here, I think we have to be careful with our definitions. I
don't think that when Intel decided to call that "virtual 8086
mode" that they meant what we mean when we're talking about with
whole-system virtualization.

- Dan C.


--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

cross@spitfire.i.gajendra.net (Dan Cross) writes:

In article <n2vpmmF46gsU1@mid.individual.net>,
Ted Nolan <tednolan> <tednolan> wrote:

In article <10qe90l$kv9$2@gal.iecc.com>, John Levine <johnl@taugh.com> wrote:

According to Peter Flass <Peter@Iron-Spring.com>:

The difference here is clear. My question is, what's the difference >>>>between emulation and simulation? Is there a difference, even if only in >>>>connotation. I'm never quite clear on whether to call something an >>>>emulator or a simulator.

The usual rule of thumb is that emulation involves hardware or microcode >>>support,
simulation is just software.

Virtualization is something else, where the architecture of the internal system
is the same as the external system so you can run the same operating system in
a virtual machine you can on the hardware, give or take very small tweaks. >>

I would say that's not quite complete, as you had the 386 being able to >>virtualize the 8086, but not itself.

Here, I think we have to be careful with our definitions. I
don't think that when Intel decided to call that "virtual 8086
mode" that they meant what we mean when we're talking about with
whole-system virtualization.

Back in 1998/1999 at SGI, I was part of an internal
skunkwork project to design and implement a hypervisor
for virtualization (code named Crucible (crux)) on an
intel Pentium Pro (Pentium II?) multiprocessor system.

We were using HP Kayak boxes for testing. Our initial
goal was to run both linux and windows NT 4.0 on the
same system simultaneously as guests of the hypervisor.

Each guest was permanently assigned to one of the CPUs.

We spent some time investigating whether the
intel virtual 8086 mode was useful for virtualization,
but in the end it turned out not to be the case.

We did get it working, but it was never productized
(about the same time VMware came out of stealth mode).

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)

rbowman <bowman@montana.com> writes:

On Thu, 02 Apr 2026 14:57:05 GMT, Scott Lurndal wrote:

We were using HP Kayak boxes for testing. Our initial goal was to run
both linux and windows NT 4.0 on the same system simultaneously as
guests of the hypervisor.

Did you have any problems with the Kayaks? It's been too long and I don't >remember the specifics but there was something about then. We used ONC RPC >and we ran into a system that was using 111 but I don't think it was the >HPs.

Not that I recall. Ours were all dual processor boxes.

--- PyGate Linux v1.5.13
* Origin: Dragon's Lair, PyGate NNTP<>Fido Gate (3:633/10)