Design and performance analysis of multistage interconnection networks using a recursive multicast algorithm

Abstract

In this paper, we study issues of the multicast communication in the multistage interconnection networks (MINs) for large-scale multicomputers. In addition to point-to-point communication among processing nodes, efficient collective communication is critical to the performance of multicomputers. Multicast communication in which the same packet is delivered from a source node to an arbitrary number of destination nodes is fundamental in supporting collective communication primitives including broadcast, reduction, and barrier synchronization operations. This paper presents a new approach to support multicast communication, on the basis of a restricted address encoding scheme which constructs a short fixed-size multicast header, and a recursive scheme that recycles a multicast packet one or more times through the MIN to send it to the desired destination nodes. We propose a recursive multicast algorithm which provides deadlock-freedom for multiple multicast packets in MIN-based multicomputers. We also present performance model for the unbuffered MIN using the multicast algorithm and analyze its performance in terms of the network throughput, where several multicast communications are considered. The proposed algorithm can be easily applied to wormhole or virtual cut-through MIN-based multicomputers.