On The Complexity Of Scheduling With Communication Delay And Contention

We show the NP-Completeness of two processor scheduling with tasks of execution time 1 or 2 units and unit interprocessor communication latency. We develop a model of scheduling in the presence of communication contention, and show the NP-Completeness of two processor scheduling with unit execution time tasks in our model. Keywords: Precedence Constrained Scheduling, Interprocessor Communication Delays, Message Contention, NP Completeness 1. Introduction We consider scheduling models in which the computation is modelled as a set of tasks which are executed independently, sequentially and non-preemptively at times which are consistent with a partial order specified as an acyclic directed graph (dag). We are interested in the case where the tasks are executed on identical processors according to the definition used by, for example, Graham et al. [1]. In scheduling models the edges in the dag imply precedence and also, in some sense data flow. If tasks connected by an edge are uniquely..

Parallel Processing Letterscfl World Scientific Publishing Company ON THE COMPLEXITY OF SCHEDULING WITH COMMUNICATION DELAY AND CONTENTION

ABSTRACT We show the NP-Completeness of two processor scheduling with tasks of execution time 1 or 2 units and unit interprocessor communication latency. We develop a model of scheduling in the presence of communication contention, and show the NP-Completeness of two processor scheduling with unit execution time tasks in our model