Extending the Strided Communication Interface in OpenSHMEM

OpenSHMEM is a library interface specification which has resulted from a unification effort among various vendors and users of SHMEM libraries. OpenSHMEM includes routines which aim to support a PGAS programming model, encompassing data management, onesided communication, atomics, synchronization, collectives, and mutual exclusion. In the work described in this paper, we investigated the usage and performance of strided communication routines. Moreover, we propose and describe an implementation for new strided communication routines, shmem iputmem and shmem igetmem, which enable a more general means for expressing communications entailing data transfers for two-dimensional subarrays or for arrays of structures. We demonstrate the use of these routines on a halo exchange benchmark for which we achieved, on average, a 64.27% improvement compared to the baseline implementation using non-strided communication routines and also 63.37% improvement compared to the one using existing strided communication routines.