A multi-core system includes multiple processor cores; a bus connected to the processor cores; multiple peripheral devices accessed by the processor cores via the bus; profile information including information concerning access of the peripheral devices by each task assigned to the processor cores; a monitor that based on the profile information, monitors access requests to the peripheral devices from tasks under execution at the processor cores and prohibits an access request that causes contention at the bus; and a scheduler that when the monitor prohibits an access request that causes contention at the bus, switches to a different task.