A Runtime Optimization System for OpenMP

Abstract. This paper introduces stOMP: a specializing thread-library for OpenMP. Using a combined compile-time and run-time system, stOMP specializes OpenMP parallel regions for frequently-seen values and the configuration of the runtime system. An overview of stOMP is presented as well as motivation for the runtime optimization of OpenMP applications. The overheads incurred by a prototype implementation of stOMP are evaluated on three Spec OpenMP Benchmarks and the EPCC scheduling microbenchmark. The results are encouraging and suggest that there is a large potential for improvement by the runtime optimization of OpenMP applications.