Exploiting unused time slots in list scheduling considering communication contention

Abstract

Static scheduling is the temporal and spatial mapping of a program to the resources of a parallel system. Scheduling algorithms use the Directed Acyclic Graph (DAG) to represent the sub-tasks and the precedence-constraints of the program to be parallelised. This article proposes an extention to the classical list scheduling heuristic that allows to schedule DAGs to arbitrary processor architectures considering link contention. In this extension, communication links are treated as shared resources likewise the processors and we improve the extended algorithm by exploiting unused time slots on the resources. The algorithm is experimentally compared to the existing heuristics BSA and DLS.