The performance and scalability of SHMEM and MPI-2 one-sided routines on a SGI Origin 2000 and a Cray T3E-600

This paper compares the performance and scalability of SHMEM and MPI-2 one-sided routines on different communication patterns for a SGI Origin 2000 and a Cray T3E-600. The communication tests were chosen to represent commonly used communication patterns with low contention (accessing distant messages, a circular right shift, a binary tree broadcast) to communication patterns with high contention (a ‘naive’ broadcast and an all-to-all). For all the tests and for small message sizes, the SHMEM implementation significantly outperformed the MPI-2 implementation for both the SGI Origin 2000 and Cray T3E-600. Copyright c © 2004 John Wiley & Sons, Ltd.