Impact of Communication Protocol on Performance

We use the PSTSWM compact application benchmark code to characterize the performance behavior of interprocessor communication on the SGI/Cray Research Origin 2000 and T3E-900. We measure 1. single processor performance, 2. point-to-point communication performance, 3. performance variation as a function of communication protocols and transport layer for collective communication routines, and 4. performance sensitivity of full application code to choice of parallel implementation. We also compare and contrast these results with similar results for the previous generation of parallel platforms, evaluating how the relative importance of communication performance has changed