What are the different properties of an operating system?

What are the different properties of an operating system?

Batch processing:- Batch processing is a technique in which Operating System collects one programs and data together in a batch before processing starts. Operating system does the following activities related to batch processing.

OS defines a job which has predefined sequence of commands, programs and data as a single unit.

OS keeps a number a jobs in memory and executes them without any manual information.

Jobs are processed in the order of submission i.e. first come first served fashion.

When job completes its execution, its memory is released and the output for the job gets copied into an output spool for later printing or processing.

main properties of an operating system


Multitasking:-

Multitasking refers to term where multiple jobs are executed by the CPU simultaneously by switching between them. Switches occur so frequently that the users may interact with each program while it is running.

Operating system does the following activities related to multitasking.

Operating system allows the users to share the computer simultaneously. Since each action or command in a time-shared system tends to be short, only a little CPU time is needed for each user.

As the system switches CPU rapidly from one user/program to the next, each user is given the impression that he/she has his/her own CPU, whereas actually one CPU is being shared among many users.

When a process executes, it typically executes for only a very short time before it either finishes or needs to perform I/O.

A program that is loaded into memory and is executing is commonly referred to as a process.

main properties of an operating system


Multi-programming:-

When two or more programs are residing in memory at the same time, then sharing the processor is referred to the multi-programming. Multi-programming assumes a single shared processor. Multiprogramming increases CPU utilization by organizing jobs so that the CPU always has one to execute.

Operating system does the following activities related to multi- programming.

The operating system picks and begins to execute one of the jobs in the memory.

Multiprogramming operating system monitors the state of all active programs and system resources using memory

management programs to ensure that the CPU is never idle unless there are no jobs.

This set of jobs is a subset of the jobs kept in the job pool.

The operating system keeps several jobs in memory at a time.

Memory layout for a multi-programming system figure:-

main properties of an operating system


Real Time System:-

Real time systems represents are usually dedicated embedded systems. Operating system does the following activities related to real time system activity.

In such systems, Operating Systems typically read from and react to sensor data.

The Operating system must guarantee response to events within fixed periods of time to ensure correct performance.


Distributed Environment:-

Distributed environment refers to multiple independent CPUs or processors in a computer system. Operating system does the following activities related to distributed environment.

OS Distributes computation logics among several physical processors.

The processors do not share memory or a clock.

Instead, each processor has its own local memory.

OS manages the communications between the processors. They communicate with each other through various communication lines.


Spooling:-

Spooling is an acronym for simultaneous peripheral operations on line. Spooling refers to putting data of various I/O jobs in a buffer. This buffer is a special area in memory or hard disk which is accessible to I/O devices. Operating system does the following activities related to distributed environment.

OS handles I/O device data spooling as devices have different data access rates.

OS maintains the spooling buffer which provides a waiting station where data can rest while the slower device catches up.

OS maintains parallel computation because of spooling process as a computer can perform I/O in parallel fashion. It becomes possible to have the computer read data from a tape, write data to disk and to write out to a tape printer while it is doing its computing task.

main properties of an operating system

 

 

 

 

 

 

 

 

 

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