This paper describes the design and implementation of the virtual memory-mapped communication model (VMMC) on a Myrinet network of PCI-based PCs. VMMC has been designed designed and implemented for the SHRIMP multicomputer where it delivers user-to-user latency and bandwidth close to the limits imposed by the underlying hardware. The goal of this work is to provide an implementation of VMMC on a commercially available hardware platform; to determine whether the benefits of VMMC can be realized on the new hardware; and to investigate network interface design tradeoffs by comparing SHRIMP with Myrinet and its respective VMMC implementation. Our Myrinet implementation of VMMC achieves 9.8 microseconds one-way latency and provides 108.4 MBytes per second user-to-user bandwidth. Compared to SHRIMP, the Myrinet implementation of VMMC incurs relatively higher overhead and demands more network interface resources (LANai processor, on-board SRAM) but requires less operating system support.

This technical report has been published as

Design and Implementation of Virtual Memory-Mapped Communication on Myrinet. Cezary Dubnicki, Angelos Bilas, Kai Li and James Philbin, in Proceedings of 11th Internat. Parallel Processing Symposium, April 1997.