Hierarchical scheduling of dynamic parallel computations on hypercube multicomputers

Abstract

In this paper a hierarchical task scheduling strategy for assigning parallel computations with dynamic structures to large hypercube multicomputers is proposed. Such computations represent a wide range of recursive and divide/conquer algorithms for which structure of the problem varies dynamically. To achieve load balancing and reduce processor contentions, the system is divided into multiple regions of processors for which the first level of scheduling is done by the host computer that spreads out the initial computations into these regions. The second level scheduling is done by a set of median processors of these regions which enable the processors of their regions to optimally balance the dynamically created load and to communicate with each other with reduced overhead. The results of an extensive simulation study are presented that exhibit the performance of the proposed strategy under different loading conditions, varying degrees of depth and parallelism, and communication costs. The proposed dual-level hierarchical scheduling is shown to outperform a well known distributed scheduling strategy. © 1994 Academic Press, Inc.