How to use swap - space ?

Swap space is an area on a high-speed storage device (almost always a disk drive), reserved for use by the virtual memory system for deactivation and paging processes. At least one swap device (primary swap) must be present on the system. Virtual memory uses disk space as an extension of main memory and since memory access is faster than disk access, using swap space has a large effect on system performance.

It is perfectly normal for the swap file or page file to grow in size, sometimes growing several hundred megs in size. Below is a listing of common Microsoft operating system swap file information; however, it is important to realize that this information may vary. Finally, by default the swap files are hidden.

Operating system Swap file name Location

Windows 3.x 386PART.PAR C:\WINDOWS
Windows 95 / 98 / ME WIN386.SWP C:\
Windows NT / 2000 / XP PAGEFILE.SYS C:\

Swap space is used in various ways by different operating systems :
- Systems implementing swapping may use swap space to hold entire process image, including the code and data segments.
- The pages that are moved out of main memory can be stored by paging systems.
- Some operating systems like UNIX allow use of multiple swap spaces. These swap spaces are generally put on separate disks, so the load placed on the I/O system by paging and swapping can be spread over the system's I/O devices.

The amount of swap space needed on a system can vary depending on the amount of physical memory, the amount of virtual memory it is backing, and the way in which the virtual memory is used.