摘要
在分析状态图工作流模型的基础上,提出了一种网格环境下多QoS(服务质量)约束的组合服务模型,根据提出的模型归纳出了动态服务调度问题的形式化描述,并提出了一种基于遗传算法的动态服务调度算法进行求解.该算法采用基于服务区域及服务实例个数的编码方式,以组合方案的有效性和组合服务的综合QoS参数的效用值作为适应度函数,从而保证组合服务调度的全局QoS要求.与其它算法进行了比较.实验结果显示该算法是可行和有效的.
Based on the analysis of state-chart workflow mo de l, a model of service composition with multiple QoS (Quality of Service) constra ints in grid is presented, the method of formal description for the dynamic serv ice scheduling problem is introduced, and a novel approach based on genetic algo rithm(GA) is proposed to optimize the service scheduling, which uses the number of service areas and service instances as the coding method and adopts the utili ty function involving the validity of service composite plan and global QoS as the fitness function. The proposed approach is verified by comparing with other algorithms. Simulation results show that the proposed GA-based approach can be a competitive choice for scheduling dynamic service composition in terms of both scheduling efficiency and the relative solution quality as compared with other algorithms.
出处
《信息与控制》
CSCD
北大核心
2005年第3期279-285,共7页
Information and Control
基金
国家863计划资助项目(2003AA413320)
关键词
服务网格
服务组合
遗传算法
服务质量
服务区域
工作流模型
service grid
service composition
genetic algorithm
QoS(quality of service)
service area
workflow model
