Although an application cannot control swapping, the user can specify whether the system can swap memory by including the MEMMAN command in the CONFIG.SYS file.
If the MEMMAN command specifies SWAP, OS/2 writes selected memory pages to the SWAPPER.DAT file whenever insufficient physical memory exists to satisfy an allocation request. This is the default choice. If the MEMMAN command specifies NOSWAP, OS/2 does not swap memory.
Note: Be aware that disabling swapping will severely limit the number of applications that the user will be able to run concurrently; if there is not enough physical memory present, OS/2 might not even boot.
The exact amount of memory available to an application depends on the amount of physical memory in the machine and the amount of free disk space on the partition that contains the SWAPPER.DAT file. The location of the SWAPPER.DAT file can be specified by including the SWAPPATH command in the CONFIG.SYS file. With the SWAPPATH command, one can specify the location of the SWAPPER.DAT file, the amount of free disk space to reserve in the partition which will contain SWAPPER.DAT, and the initial size of SWAPPER.DAT. OS/2 adjusts the size of SWAPPER.DAT as necessary, leaving other files on the drive and the requested free space untouched.