What are page outs?

Answer 1

A page out is when a page from memory is written to disk. If you have a program/application that needs alot of computer memory, the CPU can break up the program and run in memory the only part it currently needs. Once that part is finished it can be paged out and the next part paged in. Using the disk drive allows the computer to run larger jobs than those that would only fit into memory. Using the disk drive to swap out pages will cause the program to run slower. It's a trade off. Today's computer has much more memory that what was available in the past and the need for paging and swaping isn't as important as it once was. It is still used today.