(Integrity servers only) VHPT_SIZE is the number of kilobytes to
    allocate for the virtual hash page table (VHPT) on each CPU in
    the system:

    o  0 indicates that no VHPT is allocated.

    o  1 indicates that OpenVMS is to choose a default size that is
       appropriate for your system configuration.

    If a VHPT is created, the smallest size is 32KB. The VHPT_SIZE
    must be a power of 2 KB in size. If the number specified is not
    a power of 2, OpenVMS chooses a VHPT size to use for your system
    that is close to the number specified.

    If insufficient memory is available during system startup,
    OpenVMS might choose a smaller size for the VHPT of each CPU.

    A summary of possible values for VHPT_SIZE is in the following
    table:

    Value Description

    0     Do not create a VHPT on each CPU.
    1     (default) OpenVMS chooses a VHPT of an appropriate size for
          each CPU.
    n     Create a VHPT of nKB for each CPU, where n is a power of
          2 that is 32 or greater. (The maximum value, however, is
          platform-dependent.)