CPU - Electrical consumption

[consithe1]

Hello everyone!

I was going through the documentation and it seems like I can't get the power consumption and electrical consumption right from the example given here.

As I understand it, the values taken in this example to calculate the consumption_profile(workload) are for the Intel Xeon E.

• The first question I have is what are a, b, c and d? What do they represent and how to "calculate" them if they are not known?

Based on the documentation, consumption_profile(workload) = a * ln(b * (workload + c)) + d
By applying this formula, I get the following results:

load_percentage	High (100%)	Medium (50%)	Low (10%)	idle (0%)	off
consumption_profile(workload)	100 W	70 W	24 W	2 W	0 W
theoretical results(found in the example)	260 W	182 W	77 W	36 W	0 W

• Do you know if I made a mistake and did not apply correctly the formula or if something is missing and was forgotten in the documentation?

Thank you for your time,
Best regards!

[da-ekchajzer]

The first question I have is what are a, b, c and d? What do they represent and how to "calculate" them if they are not known?

a, b, c are the parameters of a logarithmic function (consumption_profile) which represent the electrical consumption of a CPU depending on his load.

The parameters have been computed through regression on Teads dataset for :

• Several model ranges
• Based on the TDP

The details can be found here : https://doc.api.boavizta.org/Explanations/components/cpu/#consumption-profile

Do you know if I made a mistake and did not apply correctly the formula or if something is missing and was forgotten in the documentation?

There is a mistake on the documentation. What you calculated is right and correspond to what the API will compute.
It has been corrected here : 6343c9f

While testing, I came up with a fuzzy matching error that also have been corrected : 4a9728f

Thank you very much for your feedback !

[da-ekchajzer]

Don't forget that this is only for CPU. You also need to take into account RAM and other consumptions on the server.

[consithe1]

Thank you very much for your reply!