文件名称：Scheduling Precedence Constrained Stochastic Tasks
文件大小：2.73MB
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更新时间：2021-04-27 11:35:33
调试；异构
Generally, a parallel application consists of precedence constrained stochastic tasks, where task processing times and intertask communication times are random variables following certain probability distributions. Scheduling such precedence constrained stochastic tasks with communication times on a heterogeneous cluster system with processors of different computing capabilities to minimizeaparallelapplication’sexpectedcompletiontimeisanimportantbutverydifficultprobleminparallelanddistributedcomputing.In this paper, we present a model of scheduling stochastic parallel applications on heterogeneous cluster systems. We discuss stochastic scheduling attributes and methods to deal with various random variables in scheduling stochastic tasks. We prove that the expected makespanofschedulingstochastictasksisgreaterthanorequaltothemakespanofschedulingdeterministictasks,whereallprocessing times and communication times are replaced by their expected values. To solve the problem of scheduling precedence constrained stochastic tasks efficiently and effectively, we propose a stochastic dynamic level scheduling (SDLS) algorithm, which is based on stochastic bottom levels and stochastic dynamic levels. Our rigorous performance evaluation results clearly demonstrate that the proposed stochastic task scheduling algorithm significantly outperforms existing algorithms in terms of makespan, speedup, and makespan standard deviation.