Library /sys$common/syshlp/sysmanhelp.hlb RESERVED_MEMORY, SHOW, Parameter  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 gs_name

    Name of the memory-resident global section associated with the
    entry being displayed within the running system. If you do not
    specify gs_system, the system displays the reserved memory for
    all registered global sections.