A lower system structure reports performance information to an upper system structure. When detecting performance deterioration of the system structure on the basis of the reported performance information, the upper system structure optimizes resource redistribution of the system structure that the upper system structure manages. If the performance is improved by the optimization in the managed system structure, the optimization results is applied to the resource control of the lower system structure, and the lower system structure redistributes the resources according to the resource control. If the performance is not improved by the optimization, the lower system structure reports the performance information to the upper system structure, which optimizes the resource redistribution.