[virtmach] Definition a virtual machine ?

Oleg Moroz moroz@metahood.ru
Wed, 17 Nov 1999 11:48:46 +0300


> How would you define a virtual machine ?
>
> I'd say that any API can be considered a virtual machine. Having
> byte-coded instructions is just an implementation issue of the VM
> after all.

Hmmm, even if we take this POV, API is only one part of execution
environment - the other (and very significant) part is the actual hardware
(or underlying VM) instruction set.

On the other hand, Mach (and other microkernels) are not pure API - they
virtualize application's attempts to access the hardware (memory, CPU, I/O
devices) directly, often in non-trivial ways, thus adding a VM-like layer.

Oleg Moroz
Software Engineer
Geonix / MetaHood