Definition:
- A process can be swapped temporarily out of memory to a backing store, and then brought back into memory for continued execution
- backing store: fast and large enought disk
- Swap out: memory from RAM to Backing Store
- Swap in: memory load from Backing Store to RAM
- Increase time for context switching
- For paging: the whole page is swap at a time
Swap Space:
- partition on the storage device that is used when the system runs out of physical memory.
- Usually, the swap space equals 1.5 x the quantity of RAM.
Types of swap
- Device swap: configured when you partition the storage device and used by the OS to run large applications.
- File system swap: configured primarily upon installing Linux and used by the OS as an emergency resource when the available swap space runs out.
- Pseudo-swap: enables large applications to run on computers with limited RAM.