[Beowulf] Re: amd 3 and 6 core processors

[Nifty Tom Mitchell]

On Mon, Aug 24, 2009 at 08:29:47AM +0200, Kilian CAVALOTTI wrote:
> 
> On Fri, Aug 21, 2009 at 12:35 AM, <richard.walsh at comcast.net> wrote:
> > I would also like to know how Intel and
> > AMD are disabling/degrading the cores.  They very like have built
> > in circuits that they can "burn out" to ensure physical incapacity. Still,
> > perhaps it is done another way.
> 
> At least for AMD's Phenom II X3, re-enabling a disabled core is a
> simple matter of changing a BIOS setting. See
> http://www.tomshardware.com/news/amd-phenom-cpu,7080.html
 

Has anyone tinkered with disabling one core at a time
and benchmarking the remaining set of cores with various
parallel tests.

I suspect that there is some asymmetry that might color processor affinity
if the locality of the disabled core can be exposed.   Things like
interrupt servicing, cache line interactions, TLB state and IO channel
latency come to mind.    I guess AMD could just tell us....


-- 
	T o m  M i t c h e l l 
	Found me a new hat, now what?