VMS Help V73 Features, System Management Features, Dedicated CPU Lock Manager (Alpha), Enabling  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    To use the Dedicated CPU Lock Manager, set the LCKMGR_MODE
    system parameter. Note the following about the LCKMGR_MODE system
    parameter:

    o  Zero (0) indicates the Dedicated CPU Lock Manager is off (the
       default).

    o  A number greater than zero (0) indicates the number of CPUs
       that should be active before the Dedicated CPU Lock Manager is
       turned on.

    Setting LCKMGR_MODE to a number greater than zero (0) triggers
    the creation of a detached process called LCKMGR_SERVER. The
    process is created, and it starts running if the number of active
    CPUs equals the number set by the LCKMGR_MODE system parameter.

    In addition, if the number of active CPUs should ever be reduced
    below the required threshold by either a STOP/CPU command or by
    CPU reassignment in a Galaxy configuration, the Dedicated CPU
    Lock Manager automatically turns off within one second, and the
    LCKMGR_SERVER process goes into a hibernate state. If the CPU is
    restarted, the LCKMGR_SERVER process again resumes operations.