HIPIQS: a high-performance switch architecture using input queuing

Switch-based interconnects are used in a number of application domains including parallel system interconnects, local area networks, and wide area networks. However, very few switches have been designed that are suitable for more than one of these application domains. Such a switch must offer both extremely low latency and very high throughput for a variety of different message sizes. While some architectures with output queuing have been shown to perform extremely well in terms of throughput, their performance can suffer when used in systems where a significant portion of the packets are extremely small. On the other hand, architectures with input queuing offer limited throughput, or require fairly complex and centralized arbitration that increases latency. We present a new input queue-based switch architecture called HIPIQS (High-Performance Input-Queued Switch). It offers low latency for a range of message sizes, and provides throughput comparable to that of output queuing approaches. Furthermore, it allows simple and distributed arbitration. HIPIQS uses a dynamically allocated multi-queue organization, pipelined access to multi-bank input buffers, and small cross-point buffers, to deliver high performance. Our simulation results show that HIPIQS can deliver performance close to that of output queuing approaches over a range of message sizes, system sizes, and traffic. The switch architecture can therefore be used to build high performance switches that are useful for both parallel system interconnects and for building computer networks.