RE: [PATCH] cpuidle/drivers/mobile: Add new governor for mobile/embedded systems

[Doug Smythies]

On 2019.07.03 08:16 Daniel Lezcano wrote:
> On 03/07/2019 16:23, Doug Smythies wrote:
>> On 2019.06.20 04:58 Daniel Lezcano wrote:

...
>> Anyway, I did a bunch of tests and such, but have deleted
>> most from this e-mail, because it's just noise. I'll
>> include just one set:
>> 
>> For a work load that would normally result in a lot of use
>> of shallow idle states (single core pipe-test * 2 cores).
>
> Can you share the tests and the command lines?

Yes, give me a few days to repeat the tests and write
it up properly. I am leaving town in an hour and for a day.

It'll be similar to this:
http://www.smythies.com/~doug/linux/idle/teo8/pipe/index.html
parent page (which I will do a better version):
http://www.smythies.com/~doug/linux/idle/teo8/index.html
...

>> I got (all kernel 5.2-rc5 + this patch):
>> 
>> Idle governor, teo; CPU frequency scaling: intel-cpufreq/ondemand;
>> Processor package power: 40.4 watts; 4.9 uSec/loop
>> 
>> Idle governor, teo; CPU frequency scaling: intel-cpufreq/ondemand;
>> Processor package power: 34 watts; 5.2 uSec/loop
>> 
>> Idle governor, mobile; CPU frequency scaling: intel-cpufreq/ondemand;
>> Processor package power: 25.9 watts; 11.1 uSec/loop
>> 
>> Idle governor, menu; CPU frequency scaling: intel-cpufreq/ondemand;
>> Processor package power: 34.2 watts; 5.23 uSec/loop
>> 
>> Idle governor, teo; CPU frequency scaling: intel-cpufreq/ondemand;
>> Maximum CPU frequency limited to 73% to match mobile energy.
>> Processor package power: 25.4 watts; 6.4 uSec/loop
>
> Ok that's interesting. Thanks for the values.
>
> The governor can be better by selecting the shallow states, the
> scheduler has to interact with the governor to give clues about the
> load, that is identified and will be the next step.
>
> Is it possible to check with the schedutil governor instead?

Oh, I already have some data, just didn't include it before:

Idle governor, teo; CPU frequency scaling: intel-cpufreq/schedutil;
Processor package power: 40.4 watts; 4.9 uSec/loop

Idle governor, mobile; CPU frequency scaling: intel-cpufreq/schedutil;
Processor package power: 12.7 watts; 19.7 uSec/loop

Idle governor, teo; CPU frequency scaling: intel-cpufreq/schedutil;
Idle states 0-3 disabled (note: Idle state 4 is the deepest on my system)
Processor package power: 36.9 watts; 8.3 uSec/loop
In my notes I wrote: "Huh?? I do not understand this result, as I had
expected more similar to the mobile governor". But I did not investigate.

Anyway, the schedutil test is the one I'll repeat and write up better.

... Doug