Optimal Period of Workload Redistribution for Dynamic Bulk Synchronous Computations in Heterogeneous Computing Systems

Abstract

In dynamic bulk synchronous computations, processors may change their workloads from phase to phase. Such workload change will possibly increase the duration of a phase and the overall parallel execution time. Therefore, it is necessary to redistribute workload at runtime to reduce the parallel time. However, such workload redistribution at runtime can be expensive and the overhead of frequent runtime workload redistribution may exceed the benefit of workload redistribution and balancing. The problem of finding the optimal period of runtime workload redistribution for dynamic bulk synchronous computations is motivated by the combined consideration of parallel execution time and system overhead for workload redistribution and balancing. We develop an analytical method to solve the problem in heterogeneous computing systems. We also demonstrate numerical data of the analytical method and simulation results that verify the analytical data.