Software Tuning, Performance Optimization & Platform Monitoring
Discussion regarding monitoring and software tuning methodologies, Performance Monitoring Unit (PMU) of Intel microprocessors, and platform updating.

Read Power Limit from CPU

Viana__Samuel
Beginner
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How can i read the power limit of a CPU from MSR, i already read the developers manual and even found some MSR that seem to hold the information that i wanted but i don't think it's right. That value would be 84 W or am i wrong.
Sorry by the English by the way.

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McCalpinJohn
Honored Contributor III
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It is pretty easy to get confused by the way the values are encoded into the MSRs.   I started with this code http://web.eece.maine.edu/~vweaver/projects/rapl/rapl-read.c and simplified it for my systems.

The code is also included in my project https://github.com/jdmccalpin/periodic-performance-counters/blob/master/perf_counters.c at lines 1403-1444.

I have not had any trouble getting the expected answers on my server processors, but I have never tried to read the configuration of client processors or processors with configurable TDP....

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Viana__Samuel
Beginner
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What i need to do is to get CPU current temperature, load, clock and power and show them in relation with the maximum values of each parameter.
The OpenHardwareMonitor lib(https://github.com/openhardwaremonitor/openhardwaremonitor) was very usefull in getting the current values but not the maximum ones, now only the power is missing. And since Intel Extreme Utility get that value i thought that it is possible.
I'll take a look on what you sent here, and get back with one answer, thanks.

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