The basic OS/2 2.0 system requires a minimum of 4MB of memory. This enables users to run applications or other system utility programs concurrently, but it presents a constrained environment (limited memory) for some large applications.
OS/2 2.0 can run concurrent applications that might require more memory than is actually available in the system. It does this by moving the least recently used pages of the operating system or other applications to disk and loading those parts of the application that are needed to perform the requested operation. This paging allows applications to go beyond the system's physical memory limitation.
In limited memory configurations, performance of applications might be reduced, particularly when the operating system is loading an application or switching from one application to another or to the desktop. This is a result of paging. When planning system memory requirements, consider the functions that the environment uses. Use Table 4 to help determine the necessary memory for the environment.