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0e1f616
(Get the code!)
CPU throttling (as opposed to later frequency/power scaling) is not expected to give us any particular power savings on CPUs supporting the C2 idles states, which the ones mentioned here should support. Obviously at any instant there may be a power saving if the cpu is running at 50% throttling as compared to 0% throttling if the CPU is under load, the maximum power the CPU can consume is constrained but so is its throughput; thus andy specific task will take longer and consume the same power overall. As a general rule any machine being used for interactive or bursty work is idle nearly all the time, and when it is idle it should be automatically placed into C2 state to conserve power. As power consumption in C2 is the same as power consumption during the 'idle' cycles introduced by throttling, overall power consumption for any bursty task from start to completion should be the same. Therefore throttling _should_ never be a benefit. Below are some references to some background I found when researching this bug:
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@kurosaki_ichigo
You pasted in some battery consumption information when using frequency throttling, which show about a 36% drop in power consumption but you do not indicate either the throtteling level used nor the test load you were running on it. Do you still have those details?