> Because nowadays people seem to think throttling is BAD for power management. > It's apparently much more efficient to IDLE as much as possible to save > power, and to do that you should be running the processor on as high speed > as possible to get whatever work you need to get done finished as soon as > possible to maximize the time that can be used for idling.
This is incorrect, or rather misleading. Throttling is the process of forcing the cpu into a HALT state with a pulse width modulator. This is generally a poor man's effort to reduce thermal load and a last ditch effort to prevent overheating, otherwise it is depreciated and not used these days. Lowering the processor frequency and voltage reduces the power consumption per clock, so even though a process takes more time to execute, it uses less energy. > herefore, powernowd is indeed obsolete, but one must change the > governor manually to "ondemand" upon purging the package, or reboot. So if you reboot, it goes to ondemand? That sounds fine. > thought that "throttling" referred precisely to changing the voltage > and frequency of the CPU, as opposed to changing the C-state? No, as I said above it just means forcing the processor into the HALT state part of the time. C-states are ACPI states that correspond to HALT and then deeper states of sleep where the cpu is not executing instructions. P-states are ACPI states that alter the cpu running frequency and voltage. Powernowd used to accomplish the same thing as ACPI P-states by directly manipulating the amd k8 cpu registers. The kernel now has drivers to perform frequency control using either ACPI, or the amd or intel cpu specific registers. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
