Load Balanced Priority

We consider eecient algorithms for priority queues on distributed memory multiprocessors, such as nCUBE, iPSc, MPP and loosely-coupled systems consisting of networked workstations. For a p-processor distributed memory multicomputer P and n data items in the priority queue, n > p, we investigate two priority queues; horizontally sliced and vertically sliced. Both of these achieve load balance, i.e. at most (n=p) data items are stored at every processor of P. Horizontally sliced priority queue allows deletions and insertions of (p) items in time O(p bw c + pp log n) on hypercubic networks where c is the communication time between a pair of processors, p is the unit processing time and bw is the width of the communication channel between a pair of processors. Vertically sliced priority queue allows deletions and insertions of (p) items in time O((c + p) log p log n) on hypercubic networks. Similar results hold for other types of networks.