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

       /PAGE_TABLES (default)
       /NOPAGE_TABLES

    Reserves additional memory for shared page tables. When the
    memory-resident global section is created, shared page tables are
    created for the global section. If you do not specify /ALLOCATE
    (or if you specify /NOALLOCATE), the additional reserved memory
    is deducted only from the system's fluid page count. If you
    specify /ALLOCATE, additional contiguous, during the next reboot
    of the system, aligned pages are allocated for the shared page
    table, and the additional reserved memory is deducted from the
    system's fluid page count.

    If you do not specify /PAGE_TABLES, or if you specify /NOPAGE_
    TABLES, additional memory is not reserved for shared page tables.
    When the memory-resident global section is created, shared page
    tables are not created for the global section.