21. One more issue is that some complex instructions are difficult to restart, e . g . following a page fault . 22. If a page is on disk, a page fault occurs and the operating system brings the page into primary storage. 23. If a program later references the evicted page, another page fault occurs and the page must be read back into RAM. 24. If the memory access time is 0.2 ?s, then the page fault would make the operation about 40, 000 times slower. 25. So if a page fault occurs, the OS can load the page from disk and then simply re-execute the faulted instruction. 26. When I click on Details it says, " RNAAPP caused an invalid page fault in module unknown at 0000 : 575c34a43. 27. A " page fault " occurs when a page is not found, and might need to be loaded from disk into memory. 28. The operating system intercepts the page fault , loads the required memory page, and the application continues as if no fault had occurred. 29. Major page faults on conventional computers ( which use hard disk drives for storage ) can have a significant impact on performance. 30. When a page fault occurs and all frames are in use, one must be cleared to make room for the new page.
