EFFICIENT MACHINE USAGE
Efficient machine usage and maximum use of the operating system resources is essential in achieving a smooth running and low cost data center. The use of Jol provides more efficient utilization of machine resources.
Catalog Management: Optionally, Catalog searching is performed at submission time and is minimized. Jol searches the catalog once regardless of the number of times a data set is used.
Tape Access Management: Jol ensures that tape data sets are left positioned correctly in cases where several data sets are created or read on one tape volume.
Reduction In Job Steps: When using the JCL Generate Option rather than Dynamic Allocation, Jol uses a transient Scheduler/Initiator so all CATALOG and SCRATCH statements can be performed in one OS step. Sometimes, several programs can be executed in the same OS job step, further reducing the OS Initiation/Termination overheads.
Reduced Overhead In Symbolic Translation: Because all Jol definitions are defined once only symbolic usage is greatly reduced. Additionally, all symbolics are resolved prior to submission greatly reducing the OS Reader/Interpreter overheads when using the JCL Generate Option.
No Hooks To The Operating System: Installation of Jol is simple and does not require an IPL. Additionally, User exits can be incorporated into Jol to enforce standards and provide User defined facilities without concern to the operating system. This ensures that an operating system upgrade does not necessitate reapplication of these exits.