Batch Operating System

Batch operating system is an operating system in which tasks are execute in a batch without any user interaction during the execution. It automatically keep executing the job in batches to reduce the setup time.

In the early job processing systems, the jobs were placed in a job queue and the memory allocated or managed by the primary memory, when space was available in the main memory, a job was selected from the job queue and was loaded into memory.

Once the job is loaded into primary memory, it competes for the processor. When the processor becomes available, the processor scheduler selects a job that was loaded in the memory and executes it. Whereas the batch strategy is implemented to provide a batch file processing. It follows that files of the similar batch are processed to speed up the task.

How Batch Operating System Works?

The users who using a batch operating system do not interact with the computer directly. Each user prepares its job on an off-line device like punch cards and submits it to the computer operator.

To speed up the processing, jobs with similar needs are batched together and run as a group. The programmers exit their programs with the operator and the operator then sorts the programs with similar requirements into batches.

Lets discuss the working of the batch operating system in the following steps −

• Step 1: Using punch cards the user prepares his job.
• Step 2: After that the user submits the job to the programmer.
• Step 3: The programmer collects the jobs from different users and sorts the jobs into batches with similar needs.
• Step 4: Finally, the programmer submits the batches to the processor one by one.
• Step 5: All the jobs of a single batch are executed together.

Features of Batch Operating System

Following are some important features of the Batch operating system which we must know about before using it −

• Job Scheduling: Jobs in batch OS are generally grouped together and can execute one after another in a pre-defined sequence. So that they can use resource very effectively.

• Automatic Job Scheduling: Batch OS automatically manages the sequence of tasks and can execute them without any interaction with the user.

• High Throughput: Batch OS generally process jobs in batches due to which the idle time of CPU is reduced and the usage of CPU is increased.

• Error Management: Batch OS provide a good error management system, it finds errors during execution of the job and reports them after the completing of the batch.

• Sequential Execution: In batch OS, jobs are generally executed in a sequence unless they are explicitly programmed.

Benefits of Batch Operating System

Following are the benefits of Batch Operating System −

• The time taken by the system to execute all the programs will be reduced.

• It can be shared between multiple users.

• It can easily handle large volumes of jobs without any constant monitoring.

• It can handle errors very effectively, means if an error found in one job, then it doesn't effect the execution of other jobs in the batch.

• It reduces turnaround time for similar type of jobs.

Limitations of Batch Operating System

Following are the limitation of Batch operating system −

• Manual interrupts are required between two batches.

• Priority of jobs is not set, they are executed sequentially.

• It may lead to starvation.

• The CPU utilization is low and it has to remain ideal for a long time because the time taken in loading and unloading of batches is very high as compared to execution time.

• No real time processing is available in the batch operating systems.