Forums - Energy and Performance overhead of using Trepn profiler

5 posts / 0 new
Last post
Energy and Performance overhead of using Trepn profiler
roshanbharathdas
Join Date: 2 Oct 16
Posts: 8
Posted: Fri, 2017-07-21 07:44

Hello,

I would like to know the overhead of using Trepn Profiler itself. What is the CPU, Memory and Energy usage of Trepn profiler when running with default setting. Is there also a way to measure it?

Thanks,

Roshan

 

  • Up0
  • Down0
ToolsPM
Join Date: 15 Feb 13
Posts: 393
Posted: Fri, 2017-07-21 10:00

Hi Roshan,

Your question is a good one. There is a way to measure this. The hardest part is the energy comparison, so I'll start with that. Since this isn't easy to do unless you have expensive hardware like a Monsoon, I'll share some data with you. Keep in mind that the load depends on the sampling rate Trepn is set to and the number of data points selected. 

- With my Nexus 6 and screen brightness set to 50%, the power with Trepn running the total system power consumed was 852mW. Without Trepn running, the total system power consumed was 754mW. That's a difference of 98mW or an increase of 13%. The load varies but in my screen brightness tests varied, but the average delta was 111mW.

- CPU load is easier to measure. Use profiling software like Snapdragon Profiler and measure the load with Trepn running and not running. The load should be less if you have a newer more powerful CPU like a Snapdragon 835. 

- Google's profiling software is good for memory measurement. 

- Rick

  • Up0
  • Down0
roshanbharathdas
Join Date: 2 Oct 16
Posts: 8
Posted: Sat, 2017-07-22 05:44

Thanks Rick,

I will measure the CPU load and memory measurement with the tools you suggested.

About the energy measurement, I don't have a monsoon tool and I was wondering for my given setting what would be the energy measurement.

My profilling interval: 100 milliseconds

Data points: only "Battery power"

Overlays: 0 (I removed all overlays).

Brightness: Off (I am basically calling the Trepn profiler from my app and I lock the screen before calling the profiler).

Phone(s): Nexus5, Nexus5x and Nexus6p. I have read from one of your earlier post that Nexus5x and Nexus6p will profile every 30 seconds for power using PMIC although I keep the profiling interval as 100 milliseconds.

Could you possibly tell me the average power consumption of Trepn profiler for the above setting? can I assume that the average delta will be 111mW?

Thanks,

Roshan

  • Up0
  • Down0
ToolsPM
Join Date: 15 Feb 13
Posts: 393
Posted: Sat, 2017-07-22 06:42

Hello Again, 

I don't have a Nexus 5, but here is my test data for a Nexus 6 with screen brightness 0, 100ms interval and no overlays. I had Battery Power and screen brightness data points, but that shouldn't make much of a difference. 

Results

- Power consumption without Trepn (Monsoon only): 494mW

- Power consumption with Trepn and Monsoon: 618mW

- Delta: 125mW

Note: This delta was higher than all of my other screen brightness values. Not sure why. Maybe Android turns off other stuff with that brightness setting. Also, keep in mind that the Nexus 5 consumes a little less power than the Nexus 6 because of the screen differences, so your phone probably uses a little less power. I think 111mW is probably a better value to use. 

If you run the other tests, please post your results here. I'm sure others would be curious to see your findings. 

- Rick

  • Up0
  • Down0
roshanbharathdas
Join Date: 2 Oct 16
Posts: 8
Posted: Sun, 2017-07-23 03:29

Okay, Thanks.

Roshan

  • Up0
  • Down0
or Register

Opinions expressed in the content posted here are the personal opinions of the original authors, and do not necessarily reflect those of Qualcomm Incorporated or its subsidiaries (“Qualcomm”). The content is provided for informational purposes only and is not meant to be an endorsement or representation by Qualcomm or any other party. This site may also provide links or references to non-Qualcomm sites and resources. Qualcomm makes no representations, warranties, or other commitments whatsoever about any non-Qualcomm sites or third-party resources that may be referenced, accessible from, or linked to this site.