Time-sharing operating systems
Time-sharing means to share the time in among processes. When there are many processes and each process wants to loads on to the memory and each process wants to execute on the CPU then what operating system can do?
Simply, the time-sharing operating system tries to satisfy every process. When there are fewer resources and many processes are waiting for getting the resources comma that time sharing is the best solution for this problem. Time-sharing operating systems equally distribute the time among each of the processes.
Time-sharing systems are the interactive systems and support the multiprocessing and multiprogramming. The time-sharing system allows multiple users to access and to share the computer concurrently. The time-sharing system can execute multiple processes together at the same time.
The time-sharing systems play a very important role when multiple computers are connected with a communication network. The time-sharing operating system can facilitate different processes to execute together. Time-sharing operating systems share the time between all the processes.
Each process is assigned a small amount of time, and this time is known as Time slice. Round Robin scheduling is a very famous scheduling algorithm of a time-sharing system. Any of the processes can execute in the CPU if a process has a time slice. When time slice of a process expires, then that process needs to leave the CPU. All this mechanism continues in a regular cycle.
Example of Time-sharing operating systems
For example, there are three users working on the same operating system, and suppose there are three processes. The process one is for user one and process 3 is for user 3. Keep in mind that the time-sharing operating system will manage all this process in such a way that every user feels that all the operating system is dedicated to him but actually it is not dedicated. We can load multiple processes together on the main memory.
When there are many processes to be load on the memory and the memory is not free, then the Operating System needs to move that process to the hard disk. Operating System maintains a job pool.
There are many examples of time-sharing operating systems. Some common examples are mentioned below; Windows 2000 server
- Windows NT server
Advantages of time-sharing operating system
- There are many advantages of time-sharing operating systems. Some of the most common advantages are mentioned below;
- The time-sharing system helps to reduce the CPU idle time.
- Time-sharing systems improve response time.
- Time-sharing system avoids duplication of software.
Disadvantages of time-sharing operating systems
- Some common disadvantages of time-sharing operating systems are mentioned below;
- When we share the time among different process, the problem of reliability can occur
- When we share the time among different process then the problem of data communication can occur.
- Some questions of security and integrity of data in time-sharing systems are still under question.
Challenges of time-sharing systems
There are some challenges for the time sharing systems
If there are multiple processes in the system, then each process can interfere with each other, and sometimes this is not a good situation.
First time sharing system was developed by IBM.