Re: vkernel migration

[Bill Hacker <wbh@xxxxxxxxxxxxx>]

Nigel Weeks wrote:
> Just an idea for thought over your next coffee...
>
> I'm if it would be to conceivably possible to move a vkernel process(and any
> sub-processes it had) to another host? It'd have to stop temporarily, or at
> least, slow down immensely while pumping all the userland data inside the
> vkernel to the other host.
>
> It might just be easier to have a vkernel powered by multiple physical
> kernels (on different machines), giving the appearance of an SMP machine
> inside the vkernel.
>
> (Insert 40,000 lines of code here...)
>
> Nige.

Hmm... there is a sort of 'left-handed' precedent..

Before Microslog got its 'one way' licensing mits on Connectix' "Virtual PC"..
one could close a VPC session in 'save state' - which preserved even the 
(virtual) program-counter of the (virtal) PC (not to mention registers, stack, 
memory) in the 'container file' along with everything else.

That container file could be-emailed half way 'round the globe, loaded on 
another VPC-equipped box, and fired up - with the cursor in the same spreadsheet 
cell as when saved. Or whatever. Whether minutes - or months - earlier.

And it fired-up fast.

MS later prevented a container created on box A from running on box B.
Or even logged-in user A and logged-in user B on the same box.

So long as the registers, caches, RAM, stack, and program counter are preserved, 
it is as portable as the (virtualized?) hardware supports.

The IP stack, OTOH, *should* get hairy - but they handle that anyway - as when a 
network cable is swapped over to a different link and IP.

Bill