[Wrf-users] Intel Xeon EM64T verus AMD Opteron?

[Jaakko Hyvätti]

On Tue, 12 Apr 2005 Timothy.Oram at noaa.gov wrote:
> indicate that we can get more bang for the buck using the AMD Opteron
> processor versus the INTEL Xeon EM64T and our contractor would prefer to
> go with the cheaper solution.  However, FSL provided us benchmark
> results and recommended the INTEL chip.

  This is interesting.  Are these results available somewhere?  It would
be good to be able to verify the benchmark setup before saying anything.
When evaluating plattform for a single application only results for that
application matter.  Was the benchmark done with WRF?  What exactly was
the memory configuration, that matters the most.  What was the parallel
configuration?

  My understanding has been that the main difference between P4 and
Opteron has not been the 64 bit architechture, but the memory
architecture.  Adding 64 bits to P4 therefore does not fix it.  AMD has
memory directly connected to each CPU, and this cuts the access latency.
Big cache may help some depending on problem size.

Jaakko Hyvätti

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