A. —A batch system is one in which jobs are bundled together with the instructions necessary to allow them to be processed without intervention.
—The basic physical layout of the memory of a batch job computer is shown below:
—
Monitor (permanently resident) |
User Space (compilers, programs, data, etc.) |
-The monitor is system software that is responsible for
interpreting and carrying out the instructions in the batch jobs.
- When the monitor starts a job, the entire computer is dedicated to the job, which then controls the computer until it finishes.
—Advantages:
-Move much of the work of the operator to the computer
-Increased performance since it was possible for job to start as soon as the previous job finished
—Disadvantages:
-Due to lack of protection scheme, one batch job can affect
pending jobs (read too many cards, etc)
Example: A job could corrupt the monitor, thus affecting pending jobs
-A job could enter an infinite loop
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