Turn grouping for efficient multicast in wormhole mesh networks

Multicast is an important collective communication in scalable parallel computers. One efficient scheme to perform multicast is multidestination messaging. In multidestination messaging, destination nodes of a multicast are partitioned into disjoint groups. Nodes in each group are reached with a multidestination message that conforms to the base routing algorithm of the system. A systematic way of partitioning the nodes is thus critical to multidestination messaging. In this paper we propose a node grouping method, called turn grouping, for partitioning the destination nodes in a multicast. Turn grouping supports any base routing algorithm derivable from the turn model. Simulations based on three turn model-based routing algorithms show that our approach performs better than the some the others