PowerD - question



  • Hi!

    I just want to make sure, if i understand correctly the PowerD settings.
    If the PowerD is not enabled, it should use the maximum CPU all the time - correct or not?

    Pfsense 2.4.4 reports with PowerD not enabled:
    Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz
    Current: 2600 MHz, Max: 2701 MHz

    Why does it not then use the maximum mhz?
    Also is Pfsense able to use CPU´s max Turbo frequency or not?

    When i was monitoring the power consumption, i saw, that when PowerD wasnt enabled, it didnt consume that much power compared to PowerD in Maximum/Hiadaptive mode.

    "grep -i speedstep /var/run/dmesg.boot" shows:
    est0: <Enhanced SpeedStep Frequency Control> on cpu0
    est1: <Enhanced SpeedStep Frequency Control> on cpu1
    est2: <Enhanced SpeedStep Frequency Control> on cpu2
    est3: <Enhanced SpeedStep Frequency Control> on cpu3


  • Netgate Administrator

    The vast majority of CPUs/boards default to running at maximum speed if there is no cpufreq control running. However some so not, such as our own ADI systems, and require powerd running to see full performance.

    The additional 1MHz shown as the maximum speed is the turbo bit used trigger turbo mode. You may need powerd running to see turbo used.

    Powerd switches the CPU between P-states to improve efficiency but modern CPUs also switch between C-states which offer even lower power consumption. The result of that is that you won't likely see much reduction in power consumption at idle, P-states only really do much with some CPU loading where C-states are not used.

    Steve