Re: [PATCH v3 linux-next] cpufreq: ondemand: Calculate gradient of CPU load to early increase frequency

[stratosk <stratosk@semaphore.gr>]

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I agree that we will have false alarms but this will not be a total waste of power since the load will be more than 50 (the default grad_up_threshold value).

So, I don't think there will be *significant* increase in power. Though, I don't know a way to prove this with numbers.

Thanks,
Stratos

Viresh Kumar <viresh.kumar@linaro.org> wrote:

>On 4 April 2013 12:17, stratosk <stratosk@semaphore.gr> wrote:
>> Why do you suspect significant increased power? With ondemand  the CPU will go down to lowest freq as soon as the load will decreased. And the measurement shows that the CPU load will decrease faster (because of faster calculation).
>
>I suspect it because we are increasing freq based on the assumption:
>"If increase in load from last calculation is more then threshold, then
>we must use high freq"..
>
>So, this rise can be false alarm multiple times and we might not see
>a load increase after moving to high freq and so we are running at
>high/max freq without any need of it. And so more power.
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