Abstract: In IaaS cloud computing,users rent one or more virtual machines with different resource configurations.However,it is difficult for users to accurately estimate the performance of the virtual machine according to the resources allocated.Thus it is hard for them to select an appropriate virtual machine according to the performance requirement of the applications.Therefore,this paper proposed to predict performance of the virtual machine according to their resources and configurations based on random forest.Further,it proposed to use genetic algorithm to search the optimal configuration of the virtual machine which can meet the performance requirement.The difference of the prediction result and the target performance are used as the fitness function.The experimental results show that the random forest model can accurately predict performance of the virtual machine.And the actual performance of the virtual machine configured according to the configuration obtained by the genetic algorithm is very close to the performance requirement,and the convergence can be achieved in a short time.

Key words: Cloud computing, Configuration optimization, Genetic algorithm, Performance prediction, Random forest, Virtual machine