paging - definition

Create account
Where to search:
Thesaurus


Dictionaries » The Free On-line Dictionary of Computing » P »

paging - definition



A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
(Non-alphabetical character)


Free Online Dictionary of Computing - FOLDOC foldoc.org

paging


 
<operating system> A technique for increasing the memory space
available by moving infrequently-used parts of a program's
working memory from RAM to a secondary storage medium,
usually hard {disk.  The unit of transfer is called a page.
 
A memory management unit (MMU) monitors accesses to memory
and splits each address into a page number (the most
significant bits) and an offset within that page (the lower
bits).  It then looks up the page number in its page table.
The page may be marked as paged in or paged out.  If it is
paged in then the memory access can proceed after translating
the virtual address to a physical address.  If the
requested page is paged out then space must be made for it by
paging out some other page, i.e. copying it to disk.  The
requested page is then located on the area of the disk
allocated for "swap space" and is read back into RAM.  The
page table is updated to indicate that the page is paged in
and its physical address recorded.
 
The MMU also records whether a page has been modified since it
was last paged in.  If it has not been modified then there is
no need to copy it back to disk and the space can be reused
immediately.
 
Paging allows the total memory requirements of all running
tasks (possibly just one) to exceed the amount of {physical 
memory}, whereas swapping simply allows multiple processes
to run concurrently, so long as each process on its own fits
within physical memory.
 
(1996-11-22)
 



Permanent link to this page: http://www.diclib.com/cgi-bin/d1.cgi?l=en&base=en_foldoc&page=showid&id=9530


Learn foreign languages chatting with us!

  • josue, 31
    Cuba, Santiago De Cuba
    Native language: Spanish
    Foreign language: English
    josue
  • lester, 27
    Honduras, Tegucigalpa
    Native language: Spanish
    Foreign language: English
    catracho 100%
    lester
  • Manuel Castillo, 55
    Venezuela, San Carlos Estado Cojedes
    Native language: Spanish
    Foreign language: English
    Manuel Cas...
  • Eliza, 18
    Colombia, Ciénaga Magdalena
    Native language: Spanish
    Foreign language: English
    Eliza
  • out, 28
    Azerbaijan, Baku
    Native language: English
    Foreign language: Russian
    I wil be glad to havee friends for talking ... I am learning language.....
    out
  • Albert Snchez, 25
    Mexico, Mexico
    Native language: Spanish
    Foreign language: English
    Albert Snc...
  • Inzhu, 24
    Kazakhstan, Aktobe
    Native language: Russian
    Foreign language: English
    My dream to depart on rest to Italy
    Inzhu
  • mohamed, 38
    Egypt, Zamora
    Native language: Arabic
    Foreign language: Spanish
    mohamed
  • biorki pikeete, 19
    Dominican Republic, Santiago
    Native language: Spanish
    Foreign language: English
    biorki pik...
  • Jhony Ruiz, 30
    El Salvador, San Salvador
    Native language: Spanish
    Foreign language: English
    Soy una persona tranquila me gusta leer mucho, tambien me gusta interactuar con los demas,,, me creo bastante sociable...
    Jhony Ruiz
  • francisco, 17
    Ecuador, Zapotillo
    Native language: Spanish
    Foreign language: Spanish
    francisco
  • adry escalona, 32
    Venezuela, Caracas
    Native language: Spanish
    Foreign language: Spanish
    Hola soy adryannis me gusta aprender nuevos idiomas y conocer nuevos amigos, soy de Venezuela!!
    adry escal...
  • Miileth Krz Gtz, 17
    Colombia, Bogotã¡
    Native language: Spanish
    Foreign language: English
    So Much My Likes Out, Going To Eat Ice Cream Film Music Media Heheh, Go A cheerful farrear am Very Spoiled Likes Chat&# 39; m A Little Photogenic
    Miileth Kr...
  • naileth serrano, 27
    Colombia, Pailitas-Cesar
    Native language: Spanish
    Foreign language: Spanish
    naileth se...
  • Luna, 17
    Mexico, Yucatan
    Native language: Spanish
    Foreign language: English, Japanese
    Luna
  • lopez mediavilla, 61
    Spain, Burgos
    Native language: Spanish
    Foreign language: English
    lopez medi...
  • toni, 22
    Mexico, Veracruz
    Native language: Spanish
    Foreign language: English
    hola a todos xd me gustaría conocer gente con la cual pueda aprender ingles la verdad es que no soy nada bueno en el idioma y por ello si alguien pudiera ayudarme a aprender le o les agradecería mucho xd
    toni
  • Anderson, 21
    El Salvador, San Salvador
    Native language: Spanish
    Foreign language: English
    Anderson
  • tiram, 24
    United States, New York
    Native language: English, Arabic
    Foreign language: English, Belarusian, Finnish
    tiram
  • yennifer chincay bazan, 18
    Peru, Trujillo
    Native language: Spanish
    Foreign language: Spanish
    yennifer c...