Материал из Xgu.ru
> >[Igor Chubin:]
> > Can I run a 64-bit HVM-domain in a 32-bit host system?
> > Dom0 domU
> > 32 32 Ok
> > 32 64 ??
> > 64 32 Ok
> > 64 64 Ok
> > As far as I can understand it is possible
> > but hypervisor (and domain0) should be PAE-enabled.
> [Tomasz Chmielewski:]
> No, it's not possible - how should that work (and why would you want to
> do it)?
> If you really need to start 64bit guests on a 32bit host, you may have
> some luck with Qemu emulation, though.
You can, in fact, run a 32-bit PAE dom0 and a 64-bit domU, provided Xen itself
is 64-bit. This might even perform better than using a 64-bit dom0, due to
various differences between x86_64 and x86_32 - it's crazy stuff.
There used to be some limitations on whether suspend / resume / live migration
worked when dom0 and domU were in different x86 modes. This restriction may
have been lifted since I last saw it mentioned.