The REALMEMSIZE option
is accepted to provide compatibility with SAS code that is written
on other platforms. The option is designed for use on platforms that
do not have the concept of REGION, and it is not an effective tuning
tool on
z/OS. Although SAS on
z/OS accepts the REALMEMSIZE option,
it does not use any value that is specified for the option.
The value of REALMEMSIZE
should not be changed from the default. Use the MEMLEAVE option for
tuning memory use on
z/OS.