CPUs supporting Intel Hardware P-states

[ECalo1]

Hi,

Would it be possible to know which CPUs supports "Intel Hardware P-states" and in particular "HWP Energy Performance Preference"? Or, the other way around, looking at the specifications I can not find HWP mentioned anywhere, is it named differently? How can I identify a CPU that supports it before buying it?

Thanks and Best Regards,

Enrico

[idata]

Hi enrico.calore,

I understand you are looking for a list of Intel® processor supporting P-States. This information does not seem to be available at intel.com web site, I am going to review this matter. This thread will be updated as news become available.Allan.

[ECalo1]

Yes,

actually I guess that P-states are available on all modern Intel processors, but I am interested in the ones supporting these flags:

• hwp: Intel Hardware P-states
• hwp_notify: HWP notification
• hwp_act_window: HWP Activity Window
• hwp_epp: HWP Energy Performance Preference
• hwp_pkg_req: HWP package-level request

Thanks and Best Regards,

Enrico

[Allan_J_Intel1]

Hi Enrico,

Thank you for your patience.

Based on the information I was able to get, I understand that all processors supporting Enhanced Intel SpeedStep Technology (EIST) support P-States and the flags you mentioned previously.

This can be confirmed at

http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-instruction-set-reference-manual-325383.pdf http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-instruction-set-reference-manual-325383.pdf

See (Table 3-8, Vol 2A 3-193)

I have filtered processor with EIST for more information:

http://ark.intel.com/Search/FeatureFilter?productType=processors&SpeedstepTechnology=true Intel® Product Specification Advanced Search

Hope this information is helpful.

Allan.

[ECalo1]

I actually initially believed the same thing, but:

I am able to run on a Intel Xeon E5-2630v3 which accordingly to this: http://ark.intel.com/products/83356/Intel-Xeon-Processor-E5-2630-v3-20M-Cache-2_40-GHz Intel® Xeon® Processor E5-2630 v3 (20M Cache, 2.40 GHz) Product Specifications should support Enhanced Intel SpeedStep Technology (EIST), anyhow /proc/cpuinfo do not reports these flags and indeed cpuid confirms:

Thermal and Power Management Features (6):

digital thermometer = true

Intel Turbo Boost Technology = true

ARAT always running APIC timer = true

PLN power limit notification = true

ECMD extended clock modulation duty = true

PTM package thermal management = true

HWP base registers = false

HWP notification = false

HWP activity window = false

HWP energy performance preference = false

HWP package level request = false

HDC base registers = false

digital thermometer thresholds = 0x2 (2)

ACNT/MCNT supported performance measure = true

ACNT2 available = false

performance-energy bias capability = true

thus I am afraid that the support for Enhanced Intel SpeedStep Technology (EIST) do not imply the support for HWP...

[idata]

Hi Enrico,

That's unfortunate. Indeed the processor supports EIST, since this feature is enabled at BIOS level, please make sure you check this option just to confirm this is enabled.Additionally, try updating to the latest computer BIOS and check again.I would like to have additional information about your system configuration. Please run the following utility and attach the results.https://downloadcenter.intel.com/download/25293/Intel-System-Support-Utility Intel® System Support Utility In order to attach files, make sure you select the "Advanced Editor" option in the top right of your reply window. You will then be presented with an attach file dialogue at the bottom of the reply.Allan.

[ECalo1]

Hi,

unfortunately Intel System Support Utility is not available for Linux... anyhow, as soon as I'll have physical access to the machine, I'll try to look in the BIOS for settings related to EIST and/or HWP... as soon as I have some news I will let you know.

Thanks and Best Regards,

Enrico

[idata]

Yes, for Linux you can run the following command:

dmidecode > nucinfo.txtThank you, please do let me know if you need further assistance with your Intel product, I will be glad to assist you.Allan.

[ECalo1]

Hi,

you can find attached to this post the output of dmidecode...

Thanks,

Enrico

[idata]

Thank you for the information. When you get access to the computer BIOS, let me know your findings.

Allan.