Abstract: Due to easy implementation,high accuracy,fast convergence,particle swarm optimization algorithm is consi-dered to have advantages in solving the problem of multi-objective optimization.Virtual machine migration selection policies are defined based on the definition of matching distance and the theory of particle swarm optimization algorithm.Moreover,the particle swarm optimization algorithm is improved by introducing the ideas of avoid list.In this way,the servers,which do not have enough remaining performance to meet the demand of the virtual machine,are added to the avoid list.Therefore,it can avoid multiple virtual machines that satisfy pareto optimal solutions to migrate to the same server,causing the resource usage rate to exceed the maximum resources limit of the node.Simulation experiment was done based on the CloudSim platform,and compared with basic particle swarm optimization algorithm,our algorithm was proved to have faster speed of convergence and choice.

Key words: Particle swarm optimization,Live migration of virtual machines,Selection policy,Avoid list