期刊名称：International Journal of Electronics Communication and Computer Engineering
印刷版ISSN：2249-071X
电子版ISSN：2278-4209
出版年度：2012
卷号：3
期号：4
页码：758-762
出版社：IJECCE
摘要：Parallel program represented by an edgedirected acyclic graph (DAG) based on homogenous processors. The objective is to minimize the execution time, evaluate and compare the performance of the individual algorithms and select the best algorithm. For this purpose various tasks scheduling algorithms are available like BNP, UNC, TDB and APB. All the models of algorithms are used in various cases where BNP is used for bounded number of processors i.e. in this case the number of processors is fixed, UNC is for unbounded number of processors i.e. where the number of processors is not fixed and it changes. For mapping the tasks onto to processor in a parallel system, DAG plays an important role. DAG represents the tasks and their computational times along with the communications times in between them. It makes easy representation of the task in graphical fashion. The execution times of tasks on multiple processors depicted using Gantt charts, help in analyzing the starting and ending times of multiple tasks. The performance factor of task scheduling algorithms is calculated using various measures which includes the Makespan, Average processor utilization, SpeedUp and the Scheduled Length Ratio. All these factors help in effectively measuring the performance of algorithms
关键词：DAG; Multiprocessor; Parallel Processing; Task Graph; List Scheduling
