A page fault (sometimes #pf or pf) is a trap to the software raised by the hardware when a program accesses a page that is mapped in the virtual address space, but not loaded in physical memory. In the typical case the operating system tries to handle the page fault by making the required page accessible at a location in physical memory or kills the program in the case of an illegal access. The hardware that detects a page fault is the memory management unit in a processor. The exception handling software that handles the page fault is generally part of the operating system.
Contrary to what the name 'page fault' might suggest, page faults are not always errors and are common and necessary to increase the amount of memory available to programs in any operating system that utilizes virtual memory, including Microsoft Windows, Unix-like systems (including Mac OS X, Linux, *BSD, Solaris, AIX, and HP-UX), and z/OS. Microsoft uses the term hard fault in more recent versions of the Resource Monitor (e.g., Windows Vista) to mean 'page fault'.
Read more about Page Fault: Handling Illegal Accesses and Invalid Page Faults, Performance
Famous quotes containing the words page and/or fault:
“There is then creative reading as well as creative writing. When the mind is braced by labor and invention, the page of whatever book we read becomes luminous with manifold allusion. Every sentence is doubly significant, and the sense of our author is as broad as the world.”
—Ralph Waldo Emerson (1803–1882)
“All the satires of the stage should be viewed without discomfort. They are public mirrors, where we are never to admit that we see ourselves; one admits to a fault when one is scandalized by its censure.”
—Molière [Jean Baptiste Poquelin] (1622–1673)