VMS Help  —  Sys Parameters, LCKMGR_MODE
    (Alpha and Integrity servers) The LCKMGR_MODE parameter controls
    use of the Dedicated CPU Lock Manager. Setting LCKMGR_MODE to a
    number greater than zero (0) indicates the number of CPUs that
    must be active before the Dedicated CPU Lock Manager is turned
    on.

    The Dedicated CPU Lock Manager performs all locking operations
    on a single dedicated CPU. This can improve system performance
    on large SMP systems with high MP_Synch associated with the lock
    manager.

    If the number of active CPUs is greater than or equal to LCKMGR_
    MODE, a LCKMGR_SERVER process is created to service locking
    operations. This process runs at a real-time priority of 63 and
    is always current.

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

    Specify one of the following:

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

    o  A number greater than zero (0) indicates the number of CPUs
       that must be active before the Dedicated CPU Lock Manager will
       turn on.

    When the Dedicated CPU Lock Manager is turned on, fast path
    devices are not assigned to the CPU used by the Dedicated CPU
    Lock Manager.

    When the Dedicated CPU Lock Manager is turned on, fast path
    devices are not assigned to the CPU used by the Dedicated CPU
    Lock Manager.

    For more information about use of the Dedicated CPU Lock Manager,
    see the OpenVMS Performance Management manual.

    LCKMGR_MODE is a DYNAMIC parameter.
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