Subject: Re: Domain 0 kernel, DAC960 and SMP
To: None <port-xen@NetBSD.org>
From: Tillman Hodgson <tillman@seekingfire.com>
List: port-xen
Date: 05/28/2006 15:46:20
On Wed, May 24, 2006 at 07:19:35PM +0200, Manuel Bouyer wrote:
> 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.

I now have it running using -current kernel src. Thanks!

> > 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.

Does this demonstrate what you were saying?:

 Name              Id  Mem(MB)  CPU  State  Time(s)  Console
 Domain-0           0       63    0  r----    297.1        
 dom1               7      127    1  -b---     11.8    9607

If so, I think I understand it now. I was somewhat confused when Domain0
didn't show multiple CPUs in dmesg, but in hindsight it makes sense that
the Xen kernel would handle the allocation of CPUs itself.

-T


-- 
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