HPF codes with `regular computations', eg EP, fare well; those with `irregular' array accesses, eg FFT1, do not.
EP (NAS benchmark) on SPARCCenter 1000 (2 
sun4d processors):
Fortran 90 on SPARCCenter 2000 takes 115s; HPF on 8 processors takes 12s.
FFT1 (ParkBench) on 1 IPX with epcf90 takes 0.3s; on 8 IPXs with pghpf takes 33s!
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