Research On Scheduling Algorithm Of Workflow Tasks In Grid

The Grid is an opened, dynamic network environment. User can submint the job to the Grid from everywhere. On the other hand, the Grid resource, user and the manage strategy can change dynamically. On these situation, the QoS based scheduling algorithm of workflow tasks in grid is faced with the tremendous challenge.In this thesis, the basic concepts of Grid and Grid workflow are introduced, and the current popular grid architecture is discribed, and the Grid workflow implementation phase in the workflow life cycle is discussed emphatically.The QoS parameters with their properties are classified, and the hierarchical structure of Grid QoS is analyzed and designed. The QoS description and the mechanism of the QoS maping are introduced.The ready queue which generated from Workflow Execution Model is combined with the extended QD-Sufferage scheduling algorithm to present a research on scheduling algorithm of workflow tasks in Grid. And through experiments that the algorithm in makespan and resource utilization is superior to other similar algorithm.The mechanism proposed in this paper accords with OGSA/WSRF standard. It is a framework established on the basis of Globus service and oriented to Grid service. The service generalization and flexibility promote the development and implement of practical Grid scheduling system.