Parallel Region Reconstruction Technique for Sunway High-Performance Multi-core Processors

The leading way to achieve thread-level parallelism on the Sunway high-performance multicore processors is to use OpenMP programming techniques. In order to address the problem of low parallel efficiency caused by high thread group control overhead in the compilation of Sunway OpenMP programs, this paper proposes the parallel region reconstruction technique. The parallel region reconstruction technique expands the parallel scope of parallel regions in OpenMP programs by parallel region merging and parallel region extending. Moreover, it reduces the number of parallel regions in OpenMP programs, decreases the overhead of frequent creation and convergence of thread groups, and converts standard fork-join model OpenMP programs to higher performance SPMD model OpenMP programs. On the Sunway 1621 server computer, NPB3.3-OMP and SPEC OMP2012 achieved 8.9% and 7.9% running efficiency improvement respectively through parallel region reconstruction technique. As a result, the parallel region reconstruction technique is feasible and effective. It provides technical support to fully exploit the multi-core parallelism advantage of Sunway's high-performance processors.