On Integrity servers, CPU_POWER_THRSH is a parameter expressed
    as a percentage. OpenVMS Integrity servers monitors how active
    each CPU is over a fixed time period. If CPU_POWER_MGMT is on
    and a CPU is idle for a period of time indicated by CPU_POWER_
    THRSH, the CPU is placed in a low-power mode if it is idle. A CPU
    returns to normal power when it receives an interrupt.
    For systems supporting real-time operations that require quick
    response time, HP recommends that this feature be turned off. Use
    of this feature can result in a small performance degradation.
    For more information, see the Intel IA-64 Architecture Software
    Developer's Manual, Volume 2: IA-64 System Architecture.
    See also the CPU_POWER_MGMT parameter.
    CPU_POWER_THRSH is a DYNAMIC parameter.