This parameter indicates the maximum amount of memory that can be used simultaneously by the BACKUP, RESTORE, and LOAD (including load recovery) utilities.
Recommendation: Use the default value unless your utilities run out of space, in which case you should increase this value. If memory on your system is constrained, you might want to lower the value of this parameter to limit the memory used by the database utilities. If the parameter is set too low, you might not be able to run utilities concurrently. You should update this parameter dynamically as needed. For a small number of utilities, set this parameter to a small value. For a large number of utilities, or for memory intensive utilities, you should set this parameter to a larger value.