Re: Xen I/O performance

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

On Tuesday 20 May 2008 16:15:35 Manuel Bouyer wrote:
> On Mon, May 19, 2008 at 11:34:37PM +0200, Christoph Egger wrote:
> > >I'm impressed. The Xen kernel did much better than I expected.
> > >Congratulations to Manuel for with excellent work.
> >
> > There's potential for even better results.
> > When libc uses "call" instead of "syscall" when running in a Xen
> > environment (Dom0 or DomU), then there's some speedup because
> > that would save the intervention of the hypervisor.
>
> But then your binaries are not compatible with a native kernel ...

Not when libc detecs the Xen environment at runtime.
This may happen via an ioctl, sysctl, syscall - whatever.

The difference would be a Xen Dom0/DomU kernel returns
"true" while GENERIC returns "false".

Christoph