[Beowulf] evaluating FLOPS capacity of our cluster
hahn at mcmaster.ca
Mon May 11 11:30:31 PDT 2009
>> Excellent. Thanks Gus. That sort of estimate is exactly what I needed.
>> I do have AMD Athelons.
right - for PHB's, peak theoretical throughput is a reasonable approach,
especially since it doesn't require any real work on your part. the only
real magic is to find the flops-per-cycle multiplier for your cpus.
basically, anything introduced since core2 has been 4 f/c (incl core2).
before that, only ia64 was 4 f/c. as others have mentioned, the ">= core2
generation" includes AMD barcelona/shanghai/etc versions (server and
desktop), as well as nehalem on the intel side.
> Typical Rmax/Rpeak ratios in Top500 are around the 80% ballpark.
80 is fairly high, and generally requires a high-bw, low-lat net.
gigabit, for instance, is normally noticably lower, often not much
better than 50%. but yes, top500 linpack is basically just
interconnect factor * peak, and so unlike real programs...
More information about the Beowulf