Saving memory by splitting modules

Program modules (42m) are loaded dynamically on demand. If a program only needs some independent functions of a given module, all module resources will be allocated just to call these functions. By independent, we mean functions that do not use module objects such as variables defined outside function or SQL cursors. To avoid unnecessary resource allocation, you can extract these independent functions into another module and save a lot of memory at runtime.

If you are using 42x libraries, it is recommended that you create libraries with the 42m modules that belong to the same functionality group. For example, group all accounting modules together in an accounting library. By doing this, programmers using the 42x libraries are not dependent from module reorganizations.

Libraries are supported for backward compatibility, it is recommended that you consider using the IMPORT FGL instruction to define module dependency and get modules loaded dynamically when needed.