Total power consumption of information-processing devices and power supply/cooling facilities is reduced to realize energy saving operation of information-processing system. The information-processing system includes information-processing devices, power supply facilities, cooling facilities and an operations management device. The operations management device is connected to the devices and the facilities and includes layout information constituted of locations and operating information of the devices and locations and environmental information of the facilities. Also, the operations management device obtains the power consumption of the devices, the power supply loss of the power supply facilities and the cooling power of the cooling facilities by using the layout information, and then allocates the workloads to the devices so as to reduce the total sum of power consumption, supply loss and cooling power.