General Questions • Re: [Software] ACPI: Invalid _PCT data

I have 2x e5-2630 V4 which is 2x 10 cores or a total of 20 cores
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I was able to eliminate the "ACPI: Invalid _PCT data" Warnings/Comments/Errors by Changing the "Enable CPU HWPM" Setting in the advance section of the BIOS from "Autonomous" to "Disabled".

At a high level from researching this setting when set to autonomous allows hardware control of CPU power. Which appears to be faster than OS controlled. So I am not sure this is really an error and it does explain why everything was still throttling correctly? As a side note this is called out in CPU2006 and CPU2017 Flag Description, links below. I am not sure it is a firmware issue like I have read throughout the internet as I was trying to figure this out. Seems to be more of an unsupported feature.
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Intel® speed shift technology
The Intel Xeon processor D-1500 product family introduced hardware power management (HWPM), a new optional processor power management feature in the hardware that liberates the operating system from making decisions about processor frequency. HWPM allows the platform to provide information on all available constraints, allowing the hardware to choose the optimal operating point. Operating independently, the hardware uses information that is not available to software and is able to make a more optimized decision in regard to the p-states and c-states. The Intel Xeon processor D-2100 product family expands on this feature by providing a broader range of states that it can affect as well as a finer level of granularity and microarchitecture observability via the package control unit (PCU). On the Intel Xeon processor D-1500 product family the HWPM was autonomous, also known as out-of-band mode, and oblivious to the operating system. The Intel Xeon processor D-2100 product family allows for this as well, but also offers the option for a collaboration between the HWPM and the operating system, known as native mode. The operating system can directly control the tuning of the performance and power profile when and where it is desired, while elsewhere the PCU can take autonomous control in the absence of constraints placed by the operating system. In native mode, the Intel Xeon processor D-2100 product family is able to optimize frequency control for legacy operating systems, while providing new usage models for modern operating systems. The end user can set these options within the BIOS; see your OEM BIOS guide for more information. Modern operating systems that provide full integration with native mode include Linux*, starting with kernel 4.10, and Windows Server* 2016.

sudo journalctl -b 0 --no-pager --grep HWP

Statistics: Posted by Aki — 2024-07-14 14:59