An apparatus obtains response information including a result of processing executed by a virtual machine operates on the first device, calculates the first value that is used to evaluate a response time from transmission of the request information to reception of the response information, calculates a ratio of processing capability of the first device to processing capability of the second device, calculates, based on the first value and the ratio, a second value that is used to evaluate a processing time until a response for a request is received when the virtual machine operates on the second device, determines the second device to be a migration destination candidate of the virtual machine when the second value is smaller than a threshold value, migrates the virtual machine that operates on the first device to the migration destination candidate to turn off the power of the first device.