The MINSTG system option
tells SAS to minimize its use of storage by returning unused storage
and deleting unused load modules at the termination of steps and pop-up
windows. This option should be used on memory-constrained systems
or when sharing the address space with other applications, such as
ISPF split-screen or multisession products. If MINSTG is in effect,
then CATCACHE= is set to 0.