RE: [timer/ticks related] dom0 hang during boot on large 1TB system

[Ian Campbell <Ian.Campbell@citrix.com>]

On Mon, 2010-01-04 at 22:07 +0000, Dan Magenheimer wrote: 
> > From: Jan Beulich [mailto:JBeulich@novell.com]
> > 
> > >>> Jeremy Fitzhardinge <jeremy@goop.org> 22.12.09 19:03 >>>
> > >On 12/22/2009 09:02 AM, Jan Beulich wrote:
> > >> No, that won't help. I'm referring to things like Dom0 
> > accesses to the
> > >> M2P table it sees, which doesn't cover even nearly all 
> > memory. I can't
> > >> say whether that can go without problem, but without 
> > closely looking
> > >> at it I don't think you can assume this would work. 
> > Likewise I would
> > >> suspect tools issues (if you use the tools from 
> > xen-unstable et al),
> > >> though I have no precise pointer right now at specific issues.
> > >>    
> > >
> > >32-bit dom0 is the standard use model for Citrix product, 
> > and I think 
> > >people tend to run it even with xen-unstable.  Its a fairly 
> > well-tested 
> > >combination.
> > 
> > But very unlikely with 1Tb of memory, don't you think?
> > 
> > Jan
> 
> Only because machines with 1TB are rare/unlikely.  I can't
> speak for the Citrix product but there is NO supported
> configuration (yet) of the Oracle VM product with a 64-bit dom0.
> In other words, if a customer is using a released Oracle VM
> product and the machine on which they are running it has 1TB
> of physical memory, they ARE using a 32-bit dom0.
> 
> However, Oracle VM always specifies a dom0_mem= Xen boot parameter.
> (which is always much smaller than 1TB).

So do XenServer and XCP, FWIW.

Ian.