Skip to main content

Time Sharing System and its Requirements

 

Time sharing system

·         Time sharing refers to the allocation of computer resources in a time dependent fashion to several program simultaneously

·         A time sharing system has many user terminals that are connected to same computer simultaneously. Using these terminal, different users can work on a system at the same time

·         Thus, it uses multi programming with a special CPU scheduling among all the last one, and then again beginning from the first one

·         In time sharing system, the CPU time is divided among all the users on schedule basis.

·         It release the CPU under any of the following three conditions:

1.       When the allotted time slice expires.

2.       When the program needs to perform I/O operation.

3.       When the execution of the program is over during the time slice

·         Thus the time sharing, when the CPU is allocated to user program, the user uses the CPU for the period of time slot.

             single user operating system  

2.      Multi user operating system 

3.       Batch processing operating system

4.      Multi programming operating system 

5.     Multi tasking operating system 

6.       Multiprocessing operating system

7.       Time sharing operating system

8.     Real time system  

Time sharing system

 

·         In time sharing system the various program can be in one of the following three stses

1.       Running: the users program currently has control of the CPU, only one user will be active at a time.

2.       Ready : the user program is ready to execute but is waiting for its turn to get the CPU. More than one user can be in ready state at a time.

3.       Blocked : the user’s program is waiting for some I/O operation. More than one user can be wait state at a time.

 

·       Requirement of time sharing system

 

Time sharing system typically the following additional hardware and software features:

 

1.       A number of terminals simultaneously connected to the system, so that multiple users can simultaneously use the system in interactive mode.

 

2.       A relatively large memory to support multi programming.

 

3.       Memory protection mechanism to prevent mechanism to prevent one jobs complete status information when the CPU is taken away from it, and restoring this information back, before the CPU is given back to it again.

 

4.       An alarm clock mechanism to send an interrupt signal to the CPU after every time slice.3.

 

5.       A special CPU scheduling algorithm, which allocates the CPU for  a very short periods, to each user process in a circular fashain.

Advantage and Disadvantage of time sharing system

1.       Reduces CPU idle time . time sharing reduce idle time of CPU and increase the utilization of CPU by switching from one program to another in rapid succession.

2.       Provides advantages of quick response time. The special CPU scheduling algorithm used in time sharing system ensure quick response time to all users.


Distributed system

·         A distributed system is a collection of processor located in geographical dispersal physical location.

·         In this system, the workhold is distributed or divided between two or more computers that are linked together by communication network . that is the different processors communicate using communication links, such as telephone lines and buses3

·         The various processors do not share memory, clock ,or peripheral devices instead each processors has its local memory.

·         The purpose of distributed system is to provide an efficient and convenient environment for sharing of resources.

·         Some example of distributed operating system are amoeba, angle, chorus, much, alpha kernel.

·         The processors in a distributed system vary in size and function. They may include small microprocessors, workstations microcomputers, mainframe computers and large general purpose computers.

Comments

Post a Comment

Popular posts from this blog

Monolithic Architecture

  Monolithic Architecture Monolith means composed all in one piece. The  Monolithic  application describes a single-tiered  software  application in which different components combined into a single program from a single platform. Components can be: Authorization — responsible for authorizing a user Presentation — responsible for handling HTTP requests and responding with either HTML or JSON/XML (for web services APIs). Business logic — the application’s business logic. Database layer — data access objects responsible for accessing the database. Application integration — integration with other services (e.g. via messaging or REST API). Or integration with any other Data sources. Notification module — responsible for sending email notifications whenever needed. Example for Monolithic Approach Consider an example of Ecommerce application, that authorizes customer, takes an order, check products inventory, authorize payment and ships ordered products. This applicat...
Post a Comment
Read more

Defination of OS(operating system) and its concepts

    What do you mean by operating system?     Definition :  An operating system is a program that act as an interface between the user of a computer and the                                      Computer hardware. Operating system is a first program that gets loaded into the memory through a process called booting. Concepts of operating system : ·                       The purpose of operating system is to provide an environment in which a user can execute program in a convenient and efficient manner. ·                       Operating system is an integrated set of program that ma...
3 comments
Read more

Layered Operating System

  Layered Operating System Layered Structure is a type of system structure in which the different services of the  operating system  are split into various layers, where each layer has a specific well-defined task to perform . It was created to improve the pre-existing structures like the Monolithic structure ( UNIX ) and the Simple structure ( MS-DOS ). Example –  The Windows NT operating system uses this layered approach as a part of it . Design Analysis : The whole Operating System is separated into several layers ( from 0 to n ) as the diagram shows. Each of the layers must have its own specific function to perform. There are some rules in the implementation of the layers as follows. The outermost layer must be the User Interface layer. The innermost layer must be the Hardware layer. A particular layer can access all the layers present below it but it cannot access the layers present above it. That is layer n-1 can access all the layers from n-2 to 0 but it canno...
Post a Comment
Read more

What is RAM and Why is it Important?

  What is RAM and Why is it Important? Random access memory (RAM) is a computer's short-term memory. None of your programs, files, or Netflix streams would work without RAM, which is your computer’s working space. But what is RAM exactly? In this article, we explain what RAM means in computer terms and why it’s important. What does RAM stand for? RAM is short for “random access memory” and while it might sound mysterious, RAM is one of the most fundamental elements of computing. RAM is the super-fast and temporary data storage space that a computer needs to access right now or in the next few moments. What is RAM and Why is it Important? Random access memory (RAM) is a computer's short-term memory. None of your programs, files, or Netflix streams would work without RAM, which is your computer’s working space. But what is RAM exactly? In this article, we explain what RAM means in computer terms and why it’s important. What does RAM stand for? RAM is short for “random access memo...
Post a Comment
Read more

System structure operating architecture

  System structure operating  architecture An operating system is a construct that allows the user application programs to interact with the system hardware. Since the operating system is such a complex structure, it should be created with utmost care so it can be used and modified easily. An easy way to do this is to create the operating system in parts. Each of these parts should be well defined with clear inputs, outputs and functions. Simple Structure There are many operating systems that have a rather simple structure. These started as small systems and rapidly expanded much further than their scope. A common example of this is MS-DOS. It was designed simply for a niche amount for people. There was no indication that it would become so popular. An image to illustrate the structure of MS-DOS is as follows − It is better that operating systems have a modular structure, unlike MS-DOS. That would lead to greater control over the computer system and its various applications. T...
Post a Comment
Read more