wiki:DataParallel/BenchmarkStatus

Version 3 (modified by gckeller, 6 years ago) (diff)

--

Status of DPH Banchmarks

Program Sequential (manually vectorised) Vectorised Parallel
DotP Order of mag. faster than list impl Same performance as seq. speedup of 2 for 2 CPUs, 4 threads
QuickSort Slower than list (fusion) Slower than seq. (why?) speedup of 1.4 on 2 CPUs
SparseVector Similar to DotP
Primes (Nesl) 15 x faster than list version NYI 20 x slower than seq (fusion?)
Primes (Simon) NYI Working NYI
BarnesHut Small bug in alg Working See seq.

General remarks:

  • I only ran a first set of benchmarks when checking for what's there. I'll run the benchmarks properly as next step
  • Fusion doesn't work well on parallel programs yet, so for all but simple examples, the parallel program performs worse than the sequential
  • The compiler doesn't exploit all fusion opportunities for QSort and BarnesHut?. Once this is fixed, they should run considerably faster.
  • Interestingly, the automatically vectorised version of qsort is quite a bit faster than the hand-flattened. Need to find out why.