Standard Article

Virtual Memory and Buffer Storage

  1. Seok Joong Hwang,
  2. Seon Wook Kim,
  3. Jong-Kook Kim

Published Online: 15 SEP 2008

DOI: 10.1002/9780470050118.ecse549

Wiley Encyclopedia of Computer Science and Engineering

Wiley Encyclopedia of Computer Science and Engineering

How to Cite

Hwang, S. J., Kim, S. W. and Kim, J.-K. 2008. Virtual Memory and Buffer Storage. Wiley Encyclopedia of Computer Science and Engineering. 1–8.

Author Information

  1. Korea University, Seoul, Korea

Publication History

  1. Published Online: 15 SEP 2008

Abstract

As more and more applications and complex applications are loaded onto computer systems, some processes may need memory large than the physical main memory while a combined number of applications/processes may also overload the allowable physical main memory. As it is not cost effective to have a huge physical memory, the virtual memory concept is used to augment that lack of memory. Virtual memory is a technique that combines the main memory and the slower storage (usually hard disk) to provide the appearance of having a larger memory than actually installed to the computer system. This technique allows the execution of processes that are larger than the physical main memory and allows more processes to be in the physical memory simultaneously. This is because all of the memory references within a process are logical addresses that are dynamically translated into physical addresses at run time, and a process may be swapped in and out of the main memory such that it occupies different regions of main memory at different times during the course of its execution. In this article, we present the concept of the virtual memory and a case study of implementation.

Keywords:

  • virtual memory;
  • physical memory;
  • virtual address;
  • physical address;
  • pages;
  • segments;
  • page table;
  • memory management unit;
  • address translation