Re: [Xen-users] differences between Para-Virtualization and Full-Virtualization?

thewird
Fri, 20 Jul 2007 08:55:25 -0000

> > Hi,
> >
> > Could someone explain me the following questions:
> >
> > Where are differences between Para-Virtualization and
> Full-Virtualization in the aspects of memory management, CPU and
> Device I/O, Network?
> >
> > How is the performance difference between them?
> >
> > Thanks
> > Songtao
> There are dozens of good documents on this. Boiled down to a few
> lines,
> full virtualization emulates the entire hardware platform of a guest
> computer. That can be effective for running an otherwise incompatible
>
> operating sytem, like Windows on a Linux server.
>
> Para-virtualization uses a customized kernel, compatible with the
> host''s
> kernel and "hypervisor", that speaks compatibly and much more
> directly
> to your host''s hardware. It''s much lighter weight, allows
memory to
> be
> re-allocated among guest domains so a server can run far more guest
> domains,, and provides a really noticeable to any guest operation
> that
> has to talk to the disk. But it requires a compatible kernel on the
> guest OS, compatible with the Xen version of the host OS.

How would one go about compiling his own compatible kernel on the guest
OS? What needs to be done to the kernel.