RE: Time skew on HP DL785 (and possibly other boxes)

[Dan Magenheimer <dan.magenheimer@oracle.com>]

> >This box uses 8 quad-core AMD chips connected via
> >hypertransport.  BUT each chip is on a separate motherboard.
> >On this system hypertransport is fast and cross-node
> >memory accesses are fast enough so that these NUMA systems
> >need not behave like NUMA systems from a memory access
> >perspective.  So Xen just views the system as a 32-cpu box
> >(other than some code in the memory allocator that tries
> >to allocate near-memory where possible, but silently falls
> >back to far-memory if necessary) and guest vcpus migrate
> >freely between the nodes.  (Correct?)
>
> Then instead user'd better to enable NUMA aware bits with Xen which
> imposes some affinity limitation but looks a reasonable model
> on large
> scale system.
>
> Thanks,
> Kevin

Hi Kevin --

Are you suggesting that only NUMA-aware guests should be
run on systems like this?  If not, what do you mean by
"NUMA aware bits"?

Thanks,
Dan