On 28-Sep-2013 11:30 AM, "Ryan" ryanphilips19@googlemail.com wrote:
Thanks, I understood it! Now, From the code, i understand that the only if the load goes beyond 95% - he scales up the frequency.
Now, If we assume the load to be 50% now and he is running at a X
Frequency.
Now, what if the load increases from 50% to 70% - Will he bump it up? Since it does not cross 95% up threshold?
In the earlier code: yes.. it will inc only if we r above 95.. In the latest code we can inc freq any time..
Coming back to the load calculation - Load is computed periodically, But he considers the total wall time or up time right and total idle time from the beginning. It is not just during the "sampling period" duration.
No.. load is calculated between samples... only
Thanks for your time.
/Ryan
On Fri, Sep 27, 2013 at 4:02 AM, Viresh Kumar viresh.kumar@linaro.org
wrote:
On 27-Sep-2013 1:55 AM, "Ryan" ryanphilips19@googlemail.com wrote:
Let me understand how the downscaling works in the older sources.
So, you mean that -
- Upthreshold = 95% down dif = 5%
so, upthreshold - down diff = 90%
if load is 85% ; cpu downscaling takes place if load is 75% ; cpu downscaling takes place and so on.
So everytime for sampling rate period - work queue checks and finds the load and downscaling takes place if less than 90%.
What i did not understand is how down diff will make the cpu remain in the same range for a longer period.
Am i missing something. could you please give a detailed answer as i struggling to understand this.
Thanks for your time.
Since my first mail, I have been travelling by an overnight bus and
sending
u mail by my phone. And it is still not that easy to type with a phone.
Suppose load is 96, we switch to max freq.. now load toggles between 90
and
100 for some time... i.e. it goes to 90, 91, 92...100... but not below
90..
Then we will not decrease and increase the freq again and again.. but
keep
running at highest freq..