False sharing elimination by selection of runtime scheduling parameters

Abstract

False sharing can be a source of significant overhead on shared-memory multiprocessors. Several program restructuring techniques to reduce false sharing have been proposed in past work. In this paper, we propose an approach for elimination of false sharing based solely on selection of runtime schedule parameters for parallel loops. This approach leads to more portable code since only the schedule parameters need to be changed to target different multiprocessors. Also, the guarantee of elimination (rather than reduction) of false sharing in a parallel loop can significantly reduce the bookkeeping overhead in some memory consistency mechanisms. We present some preliminary experimental results for this approach.