Functions of Operating System | OS Tutorials

Functions of an operating system include: Memory Management, Processor, and Input/Output devices depends on the quality of its internal system and the hardware it uses to connect with the external world.

Functions of the Operating System

1. Memory Management
2. Processor Management
3. Device Management
4. File Management
5. Security Management
6. Control over system performance
7. Job accounting
8. Error detection & Response
9. Booting the computer
10. Coordination between other software and users

Let’s see each of the functions in detail.

Memory Management: Memory management refers to the management of Primary Memory or Main Memory. An Operating System does the following activities for memory management: the OS keeps track of primary memory, i.e., what part of it are in use by whom, what part are not in use. In multi-programming, the OS decides which process will get memory when and how much. OS allocates the memory when a process requests it to do so. It de-allocates the memory when a process no longer needs it or has been terminated.

Processor Management: In a multi-programming environment, the OS decides which process gets the processor when and for how much time. This function is called process scheduling. An Operating System does the following activities for processor management: the OS keeps track of the processor and the status of processes. OS allocates the processor (CPU) to a process. It deallocates the processor when a process is no longer required.

Device Management: An Operating System manages device communication via its respective drivers. It does the following activities for device management: Keeps track of all devices. The program responsible for this task is known as the I/O controller. Decides which process gets the device when and for how much time. OS allocates the device most efficiently. It de-allocates devices most efficiently.

File Management: A file system is normally organized into directories for easy navigation and usage. These directories may contain files and other directories. An Operating System does the following activities for file management: Keeps track of information, location, uses, status, etc. The collective facilities are often known as a file system. OS decides who gets the resources. It allocates the resources and also de-allocates the resources when not in need.

Security: OS prevents unauthorized access to programs and data. For shared or public systems, the OS controls access to the system as a whole and to specific system resources.

Control over system performance: OS will collect usage statistics for various resources and monitor performance parameters such as response time, recording delays between requests for a service, and response from the system.

Job accounting: OS keeps track of time and resources used by various jobs and users. On any system, this information is useful in anticipating the need for future enhancements and in tuning the system to improve performance, and can be used for job accounting purposes.

Error detection & Response: A variety of errors can occur while a computer system is running. These include internal and external hardware errors, such as a memory error, a device failure or malfunction, and various software errors. In each case, the OS must provide a response that clears the error condition with the least impact on running applications. The response may range from ending the program that caused the error, to retrying the operation, to simply reporting the error to the application, Production of dumps, traces, error messages, and other debugging and error-detecting codes.

Booting the computer: Booting is the process of starting or restarting the computer. If a computer is switched off completely and then turned on, then it is cold booting. If the computer is restarted, then it is warm-booting. Booting of the computer is done by the OS.

Coordination between other software and users: An OS enables coordination of hardware components, coordination, and assignment of compilers, interpreters, assemblers, and other software to the various users of the computer systems.