Fulcrum's FocalPoint FM4000: A scalable, low-latency 10 GigE switch for high-performance data centers

Abstract

The convergence of different types of networks into a common data center infrastructure poses a superset challenge on the part of the underlying component technology. IP networks are feature-rich, storage networks are lossless with controlled topologies, and transaction networks are low-latency with low jitter, parallel multicast. A successful Converged Enhanced Ethernet (CEE) switch should pass the domain specific network tests, and demonstrate these disparate capabilities at the same time, while maintaining traffic separation. The FocalPoint FM4000 Ethernet switch chip was designed and architected both to provide a rich Ethernet feature set and maintain the highest performance around corner cases. It achieves this through the use of a full-rate shared memory, parallel multicasting, switch architecture along with deeply pipelined frame processing. It implements traditional Ethernet, layer-3/4, and the new CEE features. In this, paper we provide an extensive performance evaluation of the FocalPoint FM4000 chip with a number of individual performance tests including, port-to-port line rate and latency, fairness of flow control under N-to-1 hotspot, and multicast line rate and latency tests. Finally, we explore the convergence by measuring the simultaneous performance of prioritized, flow-controlled unicast traffic and provisioned multicast traffic against the backdrop of full-rate best effort stressing traffic. The experimental results show that the FocalPoint FM4000 switch provides an impressive flow-through latency of only 300 nanoseconds, which is insensitive to the packet size. The FM4000 delivers optimal performance under hot-spot communication with a degree of fairness above 98%, and provides an upper bound for latency in prioritized multicast, ranging from 1.2 to 4.3 microseconds, depending on the average size of the background best-effort traffic. A direct comparison with non-prioritized multicasts, shows a performance speedup ranging from 29 to 38 times. © 2009 IEEE.