In computer operating systems, demand paging (as opposed to anticipatory paging) is a method of virtual memory management. In a system that uses demand paging, the operating system copies a disk page into physical memory only if an attempt is made to access it (i.e., if a page fault occurs). It follows that a process begins execution with none of its pages in physical memory, and many page faults will occur until most of a process's working set of pages is located in physical memory. This is an example of lazy loading techniques.
Read more about Demand Paging: Basic Concept, Advantages, Disadvantages
Famous quotes containing the word demand:
“It is not enough to demand insight and informative images of reality from the theater. Our theater must stimulate a desire for understanding, a delight in changing reality. Our audience must experience not only the ways to free Prometheus, but be schooled in the very desire to free him. Theater must teach all the pleasures and joys of discovery, all the feelings of triumph associated with liberation.”
—Bertolt Brecht (1898–1956)