Execution and the Dictionary Facility

Exactly how the dictionary facility is used at runtime depends on the status of the program.

If the program is in Test status when the program is run, the program entity‑occurrence is retrieved from the dictionary facility, and the date/time stamps are checked.
The first time any related programs are called, the entity-occurrences of these programs and of their resources must also be retrieved from the dictionary facility, their date/time stamps checked, and table entries built.
If the program is in Production status and the PROD keyword is specified with the RUN command (for example, RUN MYPROG VER PROD) or specified as the default (by SET VERSION PROD), no dictionary facility access takes place.
If the program is in Production status but the PROD keyword is not specified with the RUN command or as the default, the program entity-occurrence needs to be retrieved, but no date/time checking is performed. Since all related programs and resources must also be in Production status, no further dictionary facility access is needed.