Task Distribution on a Butterfly Multiprocessor

Abstract

We consider the practical performance of dynamic task distribution on a multiprocessor, where overloaded processors dispense tasks to be performed on idle ones which are free to execute them. We propose a topology and an algorithm for routing packets in a network from an arbitrary subset of processors S to an arbitrary subset T, where the exact target node within T for a particular task is unimportant and therefore not specified. The method presented achieves work distribution in O(10* log N) time, where N is the nodes (processors) number. It operates on a Duplex Butterfly, and requires O(log N) size buffers. The solution is dynamic, taking into consideration real time availability of processors, and deterministic. The mechanism includes throttling of the task generation rate. “Software synchronization” in asynchronous mode ensures the insensitivity of the algorithm to hardware propagation delays of signals in large networks.