VMS Help Sys Parameters, PAGTBLPFC  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    PAGTBLPFC specifies (in pages) the maximum number of page tables
    to read to satisfy a fault for a nonresident page table.

    This special parameter is used by Compaq and is subject to
    change. Do not change this parameter unless Compaq recommends
    that you do so.