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What is virtual memory-computer world

                What is virtual memory

Virtual memory 

A memory can address more memory then the amounts of physically installed on the system. This extra memory is called virtual memory. In computing virtual memory is a memory management technique that is implemented using both hardware and software. It maps memory addresses used by a program, called virtual addresses, into physical address in Computer memory. Virtual memory is a technique that allows the execution of processes which are not completely available in the memory. The main advantage of the scheme is that program can be larger than physical memory. Virtual memory serves two purpose

  • Allow us to extend the use of physical memory by using hard disk.
  • It allow us to have memory protection because each virtual address is translated to a physical address.

The size of virtual storage is limited by the addressing scheme of the computer system and the amount of secondary memory is available in storage location. In this schemes, instead of loading one long process in the main memory, the operating system both the various part of more than one process in the main memory. Virtual memory is commonly complemented by the demand paging.



Motherboard and its use

system buses in computer

CPU scheduling in operating system

Trap and Interrupt in operating system

 Advantage of DBMS and Disadvantage of DBMS

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