/sys$common/syshlp/helplib.hlb Sys Parameters, VCC_MINSIZE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    (VAX only) VCC_MINSIZE sets the lower limit in pages of memory
    used by virtual I/O cache.

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