Basic HTML version of Foils prepared 10 Sept 1996

Foil 50 Implication of Hardware Performance

From New CPS615Master Foils-- 26 August 96 Basic Simulation Track for Computational Science CPS615 -- Fall Semester 96. by Geoffrey C. Fox
tcomm = 4 or 8 /Speed in Mbytes sec
  • as 4 or 8 bytes in a floating point word
tfloat = 1/Speed in Mflops per sec
Thus tcomm / tfloat is just 4 X Computation Speed divided by Communication speed
tcomm / tfloat is 26.7, 85, 1.5, 9.35, 8, 5, 25.6, 8 for the machines SP2, iPSC860, Paragon, KSR-1, Meiko CS2, Parsytec GC, TMC CM5, and Cray T3D respectively
Latency makes situation worse for small messages and double for 64bit arithmetic natural on large problems!

© on Tue Oct 7 1997