关键词: 云工作流, 调度, 可靠性, 动态优先级, 服务质量, 萤火虫算法

Abstract: To improve the user satisfactory and reduce the operating costs,three important attributes of Quality of Service (QoS) which included time,costs and reliability were taken into account.To solve the scheduling problem of cloud workflow with minimized cost and constrains between time and reliability,an optimal scheduling approach based on firefly algorithm and dynamic priorities was proposed.The position,distance and updating mode of position in firefly algorithm were redefined and the priorities were dynamically set for task order to reduce the overall completion time.The experimental results conducted on WorkflowSim demonstrated that the proposed approach was superior to the traditional cloud workflow scheduling algorithm with regard to both the convergence speed and the obtained optimal value.

Key words: cloud workflow, scheduling, reliability, dynamic priority, quality of service, firefly algorithm