Sub System
From MidrangeWiki
The 400 comes with specialized environments for managing various types of work or functions such as:
- Interactive Processing QINTER
- Short Transactions
- Batch Processing QBATCH
- Complicated heavy Data Base Access
- Spooling QSPL
- minimal resource vs. Printers
- Communications QCMN
Think of SubSystems as the Jobs that run other Jobs. They monitor and direct what resources needed, such as CPU, pools of main storage, disk space, how many concurrent jobs allowed, type of resources they may use.
Sources of work for each subsystem
- Autostart jobs
- Work stations of users
- Jobqueues JOBQ
- Communications
Just as SubSystems manage the other jobs, the Subsystems themselves need to be managed, for optimum performance.
A simple 400 system can be managed by QBASE, while a more sophisticated system load needs QCTL.