QoS Scheduling Algorithm Based on Hybrid Particle Swarm Optimization Strategy for Grid Workflow

The service oriented grid workflow has been a research focus in grid technology. As an NP complete problem, grid service scheduling is difficult to solve by means of classic algorithms This paper presents an algorithm HPSOA (hybrid particle swarm optimization algorithm) to resolve dynamic Web services selection with QoS global optimal in grid workflow.The essence of the algorithm is that the problem of dynamic Web Service selection with QoS global optimal is transformed into a multi-objective services composition optimization with QoS constraints. The operations of the cross and mutation in genetic algorithm are brought into PSOA (particle swarm optimization algorithm) to form a mix algorithm, which called HPSOA solve the QoS global optimal problem. Theoretical analysis and experimental results indicate the feasibility and efficiency of the algorithm.