A controller apparatus obtains job history information including execution records of one or more jobs not registered in a scheduler. Based on the job history information, the controller apparatus then estimates resource usage during execution time periods initially scheduled for jobs registered in the scheduler. This resource usage includes that of at least one of the jobs not registered in the scheduler which is to be executed together with the registered jobs on an information processing apparatus. When the estimated resource usage satisfies predetermined conditions, the controller apparatus schedules jobs including the registered jobs and the at least one of the non-registered jobs.