Monday, June 2, 2014

Flux Flop Rate Summer 2014

Every so often we get requests for "How fast is Flux"?  We do have an idea, but for technical and historical reasons there is no Top500 run for flux. Based on the most recent list (November 2013) Flux would easily fall in the top 200 machines in the world with an Rpeak of 302 TFlop/s.

Computers are normally measured in Flops a measure of how many adds/multiples etc. a system could reach per-second on floating point numbers. In scientific computing we normally are interested in Double Precision numbers. In general if you are using Single Precision, or Floats, performance and available memory will be double.  This isn't the same in all cases, eg. see the Nvidia Tesla K10 (GK104, 4,580 SP GFlops, 190 DP GFlops).

So how fast is each part of Flux:

Purchasenode ct.core/nodecoresclock GhzDP flop/hzDP GFlops
flux11711220522.67421,915
flux21691220282.67421,659
flux31681220162.67421,531
flux41241619842.6841,267
flux51241619842.6841,267
flux61442028802.8864,512
Private 2602012002.8826,880
Private 312202402.885,376
Private-phi188,088
Private 11361621762.6845,261
fluxm15402002.2741,816
fluxm25321602.483,072
flux-g (k20x)5852,400
flux Phi188,088
Total16920TOTAL302,644  

Highlights:
  • Anything in Italics is entering service, and is not yet available
  • The highlighted elements are accelerators (GPU's or Phi's)
  • The 40 K20x GPU's in FluxG are faster than Flux1 and Flux2 combined, at %9 the cost
  • Machines marked Private are part of FOE
  • Machines flux4 or newer support the AVX instruction, which doubled the performance of vectorized codes.