The scheduling of tasks within a parallel program onto the underlying available processors has been studied for some time. To date, solutions to this problem generally assume that communication only occurs at the start or end of each parallel task, i.e., the child task can only start its execution when all its parent tasks complete and have sent data to it. This is termed "non-preemptive task scheduling". This paper examines the problem of the preemptive parallel program which is represented by a preemptive task model. A new preemptive scheduling algorithm, named PET, is also proposed. Experiments are conducted to illustrate the performance achievable through preemptive task execution and scheduling. Keywords: preemptive task scheduling, preemptive task execution, parallel programming. 1 Introduction The scheduling of tasks within a parallel program aims to optimize system performance via the efficient arrangement of the tasks onto the underlying available processors within the paral...

. Algorithms for the scheduling of tasks within a parallel program onto available processors generally assume that communication only occurs at the start or end of each task, i.e., a task can only commence execution when all necessary data has been sent to it. This is termed "non-preemptive task scheduling". This paper examines the problem of the preemptive parallel program which is represented by a preemptive task model. A new preemptive scheduling algorithm, named PET, is proposed. Experiments are conducted to illustrate the performance achievable through preemptive task execution and scheduling. 1 Introduction The scheduling of tasks within a parallel program aims to optimize system performance via the efficient arrangement of the tasks onto the underlying available processors within the parallel system. The task scheduling problem can be decomposed into four major aspects: the scheduling objective is the performance measure to be optimized; the task model portrays constituent task...