Simple batch system of operating system?

Answer 1

Early computers were run from console. The card readers and tape drives were input devices. Line printers, tape drives and card punched were common output devices. The user did not interact directly with computer system. The user prepared a job that consisted of program, data and some control information (control cards). He then submitted it to the computer operator in the form of punched cards.

The operating system was simple. Its basic job was to transfer control automatically from one job to the next. The operating system was always resident in memory. The operator .batched similar jobs together and then ran in the computer to speed up the processing.

The CPU is often idle in this environment as speed of I/O devices is much slower than CPU. Alter sometime, the introduction of disk instead of card reader resulted in faster I/O devices.

In disk technology, the operating system keeps all jobs on a disk instead of card reader. The resources are utilized and jobs are performed more efficiently with the help of job scheduling. Job scheduling is possible because all jobs are present on the disk.

The memory contains operating system in one part and user program in other part. The user space can contain only one process at a time in batch systems. Digital equipment's VMS is an example of a batch operating system.