What is virtual memory in operating system?

Virtual memory is a feature of an operating system that enables a computer to be able to compensate shortages of physical memory by transferring pages of data from random access memory to disk storage. This process is done temporarily and is designed to work as a combination of RAM and space on the hard disk.

Where is virtual memory in OS?

A computer can address more memory than the amount physically installed on the system. This extra memory is actually called virtual memory and it is a section of a hard disk that’s set up to emulate the computer’s RAM.

Why do we need virtual memory in OS?

The main advantage of virtual memory is that an OS can load programs larger than its physical memory. It makes an impression to the users that the computer has unlimited memory. It also provides memory protection. In order to realize the mapping operations, virtual memory needs to use page tables and translations.

How does virtual memory work in a computer?

It is a technique that is implemented using both hardware and software. It maps memory addresses used by a program, called virtual addresses, into physical addresses in computer memory. All memory references within a process are logical addresses that are dynamically translated into physical addresses at run time.

How is memory used in an operating system?

The OS puts the interrupted process in a blocking state. For the execution to proceed the OS must bring the required page into the memory. The OS will search for the required page in the logical address space.

Where does the memory go in a steady state operating system?

In the steady state practically, all of main memory will be occupied with process’s pages, so that the processor and OS has direct access to as many processes as possible. Thus when the OS brings one page in, it must throw another out.

Can a process be swapped in and out of the main memory?

This means that a process can be swapped in and out of main memory such that it occupies different places in main memory at different times during the course of execution. A process may be broken into number of pieces and these pieces need not be continuously located in the main memory during execution.