"Paging" redirects here. For paging as a form of telecommunications, see pager. For other uses, see Page.
Not to be confused with Bank switching.
See also: Page (computer memory) and Virtual memory § Paged virtual memory
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In computer operating systems, memory paging (or swapping on some Unix-like systems) is a memory management scheme by which a computer stores and retrieves data from secondary storage[a] for use in main memory.[citation needed] In this scheme, the operating system retrieves data from secondary storage in same-size blocks called pages. Paging is an important part of virtual memory implementations in modern operating systems, using secondary storage to let programs exceed the size of available physical memory.
For simplicity, main memory is called "RAM" (an acronym of random-access memory) and secondary storage is called "disk" (a shorthand for hard disk drive, drum memory or solid-state drive, etc.), but as with many aspects of computing, the concepts are independent of the technology used.
Depending on the memory model, paged memory functionality is usually hardwired into a CPU/MCU by using a Memory Management Unit (MMU) or Memory Protection Unit (MPU) and separately enabled by privileged system code in the operating system's kernel. In CPUs implementing the x86 instruction set architecture (ISA) for instance, the memory paging is enabled via the CR0 control register.
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debugging. Demand paging When pure demand paging is used, pages are loaded only when they are referenced. A program from a memory mapped file begins...
strictly on paging rather than a combination of paging and segmentation.[citation needed] Nearly all current implementations of virtual memory divide a virtual...
requested page so the program can use it. This is known as demand paging. Modern MMUs generally perform additional memory-related tasks as well. Memory protection...
systems, demand paging (as opposed to anticipatory paging) is a method of virtual memory management. In a system that uses demand paging, the operating...
more visible to the programmer than paging alone. Segments may be created for program modules, or for classes of memory usage such as code segments and data...
Valley Page (computer memory), a block of virtual memoryPaging, a method of data retrieval Bank switching, sometimes known as paging Electronic page, formatting...
number of paging requests to and from the auxiliary storage. In a virtual memory compression system, pages to be paged out of virtual memory are compressed...
operating system that uses paging for virtual memory management, page replacement algorithms decide which memorypages to page out, sometimes called swap...
terms RAM, main memory or primary storage. Archaic synonyms for main memory include core (for magnetic core memory) and store. Main memory operates at a...
general memory hierarchy structuring. Many other structures are useful. For example, a paging algorithm may be considered as a level for virtual memory when...
whether some file pages (for example executable or library files) are present in the cache or not. Demand paging Cache (computing) PagingPage replacement algorithm...
Volatile memory, in contrast to non-volatile memory, is computer memory that requires power to maintain the stored information; it retains its contents...
Introduction to Paging TLBs Advanced Page Tables CNE Virtual Memory Tutorial, Center for the New Engineer George Mason University, Page Tables "Art of...
of the available memory locations without having to resort to any sort of bank switching, memory segmentation or paging schemes. Memory management and address...
call that maps files or devices into memory. It is a method of memory-mapped file I/O. It implements demand paging because file contents are not immediately...
allows system software to use features such as segmentation, virtual memory, paging and safe multi-tasking designed to increase an operating system's control...
addresses are created in real mode, but are subject to protected mode's memorypaging mechanism. The virtual 8086 mode is a mode for a protected-mode task...
1960s as computer memory. Many early computers, called drum computers or drum machines, used drum memory as the main working memory of the computer. Some...
Core rope memory is a form of read-only memory (ROM) for computers. It was used in the UNIVAC I (Universal Automatic Computer I) and the UNIVAC II, developed...
Semiconductor memory is a digital electronic semiconductor device used for digital data storage, such as computer memory. It typically refers to devices...
and GS. In paging the memory address space or segment is divided into equal-sized blocks called pages. Using virtual memory hardware, each page can reside...
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