Question How to to calculate the equivalent utilization to each CPU speed clock. (for modeling purpose)

Oct 28, 2019
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I am working on modeling to investigate the power consumption. I have no programme running on real machine to obtain the utilisation or power usage. I am using a modeling language and assuming the server CPU is AMD with following info:



pstatePowerClock speedVoltage
0952600140
1902400135
2762200130
3652000125
4551800120
5321000110
Idle15--------


I want anyone to help me to calculate the utilization that is related to each clock speed.
is there any formula can be used ?

is it correct for example to say the utilization at a (clock speed x) =x/maxclockspeed?

for example: what is might be the utilization when CPU clock speed = 2000?
 

Aeacus

Titan
Ambassador
CPU frequency has nothing to do with CPU utilization since CPU frequency doesn't scale with CPU utilization. E.g at 2 GHz (2000 Mhz), CPU can be utilized 10%, 50% or even 100% depending on the task given to CPU.
Higher CPU frequency can shorten the time needed to complete the task at hand but that isn't always true. Efficiency is another critical part getting the task done. Efficiency is measured in terms of instructions per cycle (IPC). A CPU with a very high clock frequency, but low IPC, may not perform as well as a CPU with a lower clock frequency and high IPC.

It's like when you try to calculate car's speed based on it's engine RPM alone. It doesn't work like that. You have to consider transmission (gear amount and gear ratios), drivetrain, rim and tire size, friction and wind resistance as well. Gravity too if going up/down hill.

To calculate CPU utilization, here's further reading with formulas,
link: https://www.eukhost.com/forums/foru...-cpu-utilization-and-how-can-it-be-calculated
 
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