Browse Prior Art Database

An Improved Swap File Allocation Algorithm

IP.com Disclosure Number: IPCOM000121382D
Original Publication Date: 1991-Aug-01
Included in the Prior Art Database: 2005-Apr-03
Document File: 1 page(s) / 27K

Publishing Venue

IBM

Related People

Rasmussen, EC: AUTHOR [+2]

Abstract

This article describes a technique for use in a computer operating system (OS) to allocate swap file space.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

An Improved Swap File Allocation Algorithm

      This article describes a technique for use in a computer
operating system (OS) to allocate swap file space.

      Previously OSs allocated enough space in the swap file to
accommodate the total amount of memory environment. Since not all
memory allocations are swappable, some of this space goes unused.

      In the technique disclosed herein the size of the swap file is
limited to the amount of swappable memory allocated. The swap file
size will reflect either the amount of overcommit or the amount of
swappable allocations, whichever is smaller.  The swap file no longer
reserves space for segments it cannot hold.

      The size of the swap file is reduced dramatically, especially
for low memory configuration personal computer systems.  The OS is
able to run more programs in a memory/disk constrained machine.

      Disclosed anonymously.