Re: Domain 0 kernel, DAC960 and SMP

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Wed, May 24, 2006 at 05:38:54PM +0200, Hubert Feyrer wrote:
> On Wed, 24 May 2006, Tillman Hodgson wrote:
> >Is building a custom Xen kernel for this as easy as adding in the
> >GENERIC.MP changes and something like this for device support?:
> 
> Read http://www.netbsd.org/Ports/xen/howto.html#pci-devices

I'd add that using a recent XEN0 kernel from the netbsd-3 branch should
have the drivers for this hardware. This has been added some weeks ago.

> 
> As for SMP, I'm not sure if Xen2 supports that.
> Support for Xen3 domU and I think dom0 is in -current. (there may be some 
> code on the netbsd-3 branch, but I forgot)

With Xen2, multiple CPUs can't be used by a single domain, but if you
have multiple domains running, the hypervisor will schedule them on different
CPUs.
The assignement is done on domain startup, you can't move a domain from one
CPU to another once started.

With Xen3, it's theorically possible to have one domain use multiple CPUs
but NetBSD doesn't support that yet. I suspect the hypervisor can move
domains from one cpu to another dynamically but I didn't try this.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
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