swap file (operating system) A file used by a program or, more often, an operating system as swap space. A swap file is usually allocated as a long contiguous section of a hard disk to reduce access time. The disk space used for a swap file can not be used for other things. Under Microsoft Windows, swap files are recommended not to exceed three times the available RAM and are usually 150 percent of the RAM size.
Last updated: 1996-11-15
