Processors change between performance states (“P-states”) very quickly to match supply to demand, delivering performance where necessary and saving energy when possible. If your server has specific high-performance or minimum-power-consumption requirements, you might consider configuring the Minimum or Maximum Processor Performance State parameter.
The values for both the Minimum and Maximum Processor Performance State parameters are expressed as a percentage of maximum processor frequency, with a value in the range 0 – 100.
If your server requires ultra-low latency, invariant CPU frequency, or the very highest performance levels, you might not want the processors switching to lower-performance states. For such a server, you can cap the minimum processor performance state at 100 percent by using the following commands:
Powercfg -setacvalueindex scheme_current sub_processor 893dee8e-2bef-41e0-89c6-b55d0929964c 100
Powercfg -setactive scheme_current
If your server requires lower energy consumption, you might want to cap the processor performance state at a percentage of maximum. For example, you can restrict the processor to 75 percent of its maximum frequency by using the following commands:
Powercfg -setacvalueindex scheme_current sub_processor bc5038f7-23e0-4960-96da-33abaf5935ec 75
Powercfg -setactive scheme_current
Note that capping processor performance at a percentage of maximum requires processor support. Check the processor documentation to determine whether such support exists, or view the Perfmon counter “% of maximum frequency” in the Processor group to see if any frequency caps were applied as desired.
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