High-Level versus Low-Level DO-Loop Parallelization: Results for One Testcase of a Multi-Block Solver on a Shared Memory Parallel Vector Computer

Within the NICE project, supported by the Dutch Foundation HPCN, the multi-block Navier-Stokes flow solver ENSOLV is being parallelized. In this article first results of the block-loop parallelization of ENSOLV are presented. We discuss the performance results of this parallelization on a 16-processor NEC SX-4, a shared memory parallel vector computer. The results are compared to those of the low-level DO-loop parallelization implemented earlier. The conclusion is that for the cases with higher number of multigrid levels, the block loop parallelization gives better speed-up, requires more memory, and gives overall less execution cost.