:PROPERTIES: :ID: 05c5d285-13cb-420b-98ba-1370be5c6c15 :mtime: 20240314093715 :ctime: 20240314093714 :END: #+title: page fault #+filetags: :operatingsystems:public:project: * Page faults - When an invalid page is referenced, it causes a [[id:b947a2bf-3ab9-4773-bd18-af189479fc2f][Software Interrupt]] to the OS – a page fault - E.g., when referenced for the first time ** Handling a Page Fault - OS handles the trap by examining another table - If invalid memory reference, then abort - If valid but not resident, find a free frame and swap the page in - Entry is now marked valid as page is in memory - After handing the fault, restart the instruction that caused the fault