Composite-Path Switching

Abstract

Hybrid switching combines a high-bandwidth optical circuit switch in parallel with a low-bandwidth electronic packet switch. It presents an appealing solution for scaling data center architectures. Unfortunately, it does not fit many traffic patterns produced by typical data center applications, and in particular, the skewed traffic patterns that involve highly intensive one-to-many and many-to-one communications. In this paper, we introduce composite-path switching by allowing for composite circuit/packet paths between the two switches. We show how this enables the datacenter network to deal with skewed traffic patterns, and offer a practical scheduling algorithm that can directly extend any hybrid-switching scheduling algorithm. Through extensive evaluations using modern datacenter workloads, we show how our solution outperforms two recently proposed state-of-the-art scheduling techniques, both in completion time and in circuit utilization.