Speculative Flow Control for High-Radix Datacenter Interconnect Routers

High-radix switches are desirable building blocks for large computer interconnection networks, because they are more suitable to convert chip I/O bandwidth into low latency and low cost than low-radix switches [10]. Unfortunately, most existing switch architectures do not scale well to a large number of ports. For example, the complexity of the buffered crossbar architecture scales quadratically with the number of ports. Compounded with support for long round-trip times and many virtual channels, the overall buffer requirements limit the feasibility of such switches to modest port counts. Compromising on the buffer sizing leads to a drastic increase in latency and reduction in throughput, as long as traditional credit flow control is employed at the link level. We propose a novel link-level flow control protocol that enables high-performance scalable routers based on the increasingly popular buffered crossbar architecture to scale to higher port counts without sacrificing performan...

• Type: Conference
• Year: 2007
• Where: IPPS
• Authors: Cyriel Minkenberg, Mitchell Gusat
• Keywords: Crossbar Architecture, Distributed And Parallel Computing, IPPS 2007, Low Latency, Port Counts