The CMS Batch Facility
The CMS batch facility allows VM users to run their jobs in batch mode by sending jobs either from their virtual machines or through the real (system) card reader to a virtual machine dedicated to running batch jobs. The CMS batch facility then executes these jobs freeing user machines for other uses.
If both the CMS batch facility and the Remote Spooling Communications Subsystem (RSCS) Networking feature are being executed under the same VM system, job input streams can be transmitted to the batch facility from remote stations by communication lines. Also, the output of the batch processing can be transmitted back to the remote station.
- Entering the BATCH parameter in the PARM field of the IPL command, or
- Specifying the NOSPROF parameter of the IPL command and entering the CMSBATCH command when the VM READ status appears.
After each job is executed, the batch facility IPLs itself, thereby providing a continuously processing batch machine. The batch processor IPLs itself by using the PARM option of the CP IPL command followed by a character string that CMS recognizes as peculiar to a batch virtual machine performing its IPL. Jobs are sent to the batch machine's virtual card reader from users' terminals and executed sequentially. When there are no jobs waiting for execution, the CMS batch facility remains in a wait state ready to execute a user job.
The CMS batch facility is particularly useful for compute-bound jobs such as assemblies and compilations and for execution of large user programs, since interactive users can continue working at their terminals while their time-consuming jobs are run in another virtual machine.
The system programmer controls the batch facility virtual machine environment by resetting the CMS batch facility machine's system limits, by writing routines that handle special installation input to the batch facility, and by writing exec procedures that make the CMS batch facility easier to use.