An image forming apparatus which implements a plurality of functions includes: storage with a prescribed storage area; an operating system which implements at least some of the functions by allocating a part of the prescribed storage area for a plurality of processes and executing the processes; and a storage area managing section which predicts an amount of consumed memory in response to generation of a job and determines whether or not the amount of consumed memory is allocable to the job in the prescribed storage area. The job is a processing target for the image forming apparatus. The amount of consumed memory is used for processing the job by the image forming apparatus. When determining that the amount of consumed memory is not allocable, the storage area managing section ends at least one process which is not used to process the job to make the amount of predicted memory allocable.