Load module structure types

Each load module used during a job step can be designed in one of three load module structures: simple, planned overlay, or dynamic. A simple structure does not pass control to any other load modules during its execution, and comes into virtual storage all at one time. A planned overlay structure may, if necessary, pass control to other load modules during its execution, and it does not come into virtual storage all at one time. Instead, segments of the load module reuse the same area of virtual storage. A dynamic structure comes into virtual storage all at one time, and passes control to other load modules during its execution. Each of the load modules to which control is passed can be one of the three structure types. Characteristics of the load module structure types are summarized in Table 1.