Hi,

>> ... if the kernel of the OS has Xen support, there will be no
>> performance penalty (only 2%-3%) (Para-virtualization). Otherwise, there
>> will be full-virtualization, and we should expect a performance loss
>> about 30% for each guest OS (like Windows).
>
> I may be wrong but I thought that the guest OS kernel only needs special
> support if the underlying CPU doesn't have virtualization support which
> pretty much all the new Intel and AMD chips have. No?

You need that CPU support if you want to do full virtualization at all.
Otherwise you can only use para-virtualization. Para-virtualization has much
better performance, but full virtualization is more flexible because you
don't need special kernel support in the guest.

- Sander



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