Re: A set of "standard" virtual devices?

H. Peter Anvin
2007-04-03T20:03:54Z

Jeremy Fitzhardinge wrote:
>
> Yes, and that's the core of the Xen netfront. But is there really much
> code which can be shared between different hypervisors? When you get
> down to it, all the real code is hypervisor-specific stuff for setting
> up ringbuffers and dealing with interrupts. Like all the other network
> drivers.
>

One thing, Jeremy, which I think is being a bit misleading here: you're
focusing on big, performance-critical stuff. Those things are going to
be the ones which has the most win to implement in hypervisor-specific
ways. Although we can offer models for some hypervisors (and G-d knows
there are enough implementations out there of virtual disk which are
almost identical), they're clearly not going to be universal.

However, there are other things; console is some, or my original
example, which was random number generation. For those, the benefit of
unification is proportionally greater, simply because the win of
anything hypervisor-specific is much smaller.

-hpa