[Beowulf] Anybody going with AMD Istanbul 6-core CPU's?

[Håkon Bugge]

Craig,

On Aug 25, 2009, at 19:09 , Craig Tierney wrote:

> As far as using threading, I doubt that threading is going to buy you
> much for WRF.  Minimal testing showed no benefit and it is more likely
> to cause confusion to the users than a small bump in speed.  We  
> would like
> to test it more in the future, but right now the users need cycles.



This is consistent with my findings in "An Evaluation of Intel’s Core  
i7 Architecture using a Comparative Approach". WRF, as embodied into  
the SPEC MPI2007 suite, ran 2% slower using threading on a single- 
node, dual-core Nehalem system. Out of the 13 apps constituting the  
suite, three ran slower (2,3, and 4%), five ran +10% faster, with  
122.tachyon excelling at a 35% speedup from threading.


Thanks, Håkon