If you do not need any of the benefits of tasking described in the preceding subsection, you can simply implement your entire application as a single program, and use only procedure entrance statements rather than procedure initiation statements. Procedure entrance uses fewer system resources than procedure initiation, and allows your application to complete faster and interfere less with other running applications.
Some of the expenses involved in initiating a procedure are
-
It takes slightly more processor time than entering a procedure.
-
It causes several hundred words of save memory to be allocated for the new process stack.
-
It causes the system to create additional system log entries, and thus adds to general system overhead.
-
It adds to the number of entries visible to the operator in a mix display. It thus tends to complicate the system operator's efforts to monitor the system.
The performance differences between entering and initiating a procedure are not great if the procedure is to be executed only once. However, for a procedure that is invoked many times, the performance loss can slow an application noticeably.
