Exploiting Gigabit Ethernet capacity for cluster applications

In this paper we report about the recently completed porting of GAMMA to the Netgear GA621 Gigabit Ethernet adapter, and provide a comparison among GAMMA, MPI/GAMMA, TCP/IP and MPICH/TCP, based on the Netgear GA621 and the older Netgear GA620 network adapters and using different device drivers, in a Gigabit Ethernet cluster of PC running Linux 2.4. GAMMA (the Genoa Active Message Machine) is a lightweight messaging system based on an active message-like paradigm, originally designed for efficient exploitation of Fast Ethernet interconnects. The comparison includes simple latency/bandwidth evaluation of the messaging systems on both adapters, as well as performance comparisons based on the NAS Parallel Benchmarks and an end-user fluid dynamics application called Modular Ocean Model (MOM). The analysis of results provides useful hints concerning the efficient use of Gigabit Ethernet with clusters of PC. In particular, it emerges that GAMMA on the GA621 adapter, with a combination of low end-to-end latency (8.5 μs) and high throughput (118.4 MByte/s), provides a performing, cost-effective alternative to proprietary high-speed networks, e.g. Myrinet, for a wide range of cluster computing applications.