PSTSWM SP3-375 Algorithm Comparison

Performance Studies using

PSTSWM


IBM SP3-375 Winterhawk II Algorithm Comparison

(transpose FFT experiment A )

Date/Person: December 12, 1999 / P. Worley
Platform: IBM SP3 at Oak Ridge National Laboratory (bobcat.ccs.ornl.gov):
     62 4-way Winterhawk II SMP nodes (375 MHz POWER3 with 8MB L2 cache)
Environment: AIX 4.3.3;   PSSP 3.1.1
Code Version: 6.6.4
Compilation Options: mpxlf -O3 -qarch=auto -qtune=auto -qcache=auto
Link Options: -bmaxdata:0x70000000
Environment Variables: export MP_SHARED_MEMORY="yes"
Math Library: ESSL
Communication Library: MPI over the switch using user space for internode communication
MPI using shared memory for intranode communication
Number of Timesteps: 12
Results:

Transpose FFT (mpi)
Algorithm Comparison
  T10L16    T10L16    T21L8     T21L32    T21L16    T42L16 
  P=32     P=16     P=8     P=32     P=16     P=8  
  optimal algorithm   swtrans  srtrans  srtrans  swtrans  swtrans  srtrans 
  (alltoallv-min)/min     0.011    0.067    0.209    0.061    0.109    0.064 
  (generic-min)/min     0.275    0.218    0.225    0.433    0.365    0.052 

Transpose FFT (combined)
Communication Library Comparisons
  T10L16    T10L16    T21L8     T21L32    T21L16    T42L16 
  P=32     P=16     P=8     P=32     P=16     P=8  
  optimal library   mpi  mpi  mpi  mpi  mpi  mpi 
  (alltoallv-min)/min     0.011    0.067    0.209    0.061    0.109    0.064 
  (mpi-min)/min     0.000    0.000    0.000    0.000    0.000    0.000 


Patrick H. Worley / ( worleyph@ornl.gov)
Last Modified Monday, 15-Jul-2002 10:19:56 EDT.