Image forming apparatus locks down storage area of cache memory stores portion of image forming program for executing real-time image forming process

An image forming device that executes an image forming program for real-time mechanical control and another program, using a single cache memory for the image forming program and said another program. The image forming device includes: a cache lockdown unit that executes a cache lockdown to lock down a storage area of the cache memory that stores at least a portion of the image forming program necessary for image formation processing; and a print unit that executes the image formation processing while the storage area is locked down.