Vectorization and parallelization of transport Monte Carlo simulation codes

Discusses the computational techniques, the coding methodology, and the performance for transport Monte Carlo simulation on vector supercomputers and on shared-memory parallel processors. A cascade shower simulation code EGS4 is used as an example. For vector processing, a more than 10-fold increase in performance has been obtained by treating the problem in a different manner from conventional sequential processing in such a way as to exploit the vector architecture of current supercomputers. For parallel processing, a more than 25-fold increase in performance has been obtained over sequential processing by using 29 processors. The authors also discuss an analytical performance model for parallel processing, issues in the parallel processing of the transport Monte Carlo codes, and comparisons between vector and parallel approaches