Achieving turbo boost, do we disable cores?

[Paul11]

Dear community,

I have been working unsuccessfully on getting an ESX server to run with turbo boost, but struggling with the BIOS settings for a particular OEM.

Right now the OEM is telling me that I need to disable cores to achieve turbo boost and that figure 1 in the "Intel Xeon Processor scalable family - specification update" indicates that only when cores are disabled can the remaining cores spin up to the full turbo boost speeds.

I don't pretend to know the deep details of this, but from my understanding the cores will spin up to turbo boost speeds when there are enough "inactive" (not disabled) cores, and the thermal and power capacity is spare to run a few cores at higher speeds.  I have configured c-states and p-states, and also enabled turbo boost in the BIOS.

At this point I need confirmation about whether it is inactive cores or disabled cores that are required for turbo boost speeds,

Thanks for your help.

[IntelSupport]

Hello Paul11

Thank you for posting in the Intel Community.

We understand that have questions about the use of Intel® Turbo Boost Technology. We would like to help you with this inquiry. To have more details about your configuration please provide us with this:

What is the brand and model of your motherboard?

What Intel® processor are you using?

What tool are you using to measure the CPU frequency?

What ESXi version are you using?

Regards,

Leonardo C.

Intel Customer Support Technician

[Paul11]

Dear Leonardo,

Thank you for your reply.

Here are the answers to your question.

• The servers (36 in total) that I would like to see turbo boost working on are Huawei 2288 V5s
• There are 2x 6252 processors in each server
• We are simply using esxtop at the moment, in combination with an md5sum running directly on the hypervisor to spin up 1 core.  I understand with esxtop is that we should see the “USER” field go up to about 175% if turbo boost is working.  We had everything set to performance initially and we could see the processor getting to 130% (the 2.8GHz achievable when all cores are running at performance)
• ESX is version 6.7

My issue is that the vendor are telling me that the turbo boost speeds are not achievable unless I start to disable cores.  My understanding of turbo boost is that it will work with all the cores active, but only requires that most of them are idle.  However, I cannot use the “my understanding” argument against a large organization, I need something from Intel saying either I need to disable cores to achieve the top turbo boost speeds, or I do not.

Just as an aside, I have enabled the p-states, and deep c-states.  In esxtop when I am running the test I can see that the majority of cores are in C2 state, which again I understand to be an extremely low power (and thermal) state and should allow for turbo boost

Best regards,

Paul

[IntelSupport]

Hello Paul11

Thank you for your response. Allow me to look into your question, I will be posting back as soon as possible.

Regards,

Leonardo C.

Intel Customer Support Technician

[IntelSupport]

Hello Paul11

Thank you for waiting.

We are working on the investigation of this issue, we are looking forward to providing updates by mid-next week.

Thank you for understanding.

Regards,

Leonardo C.

Intel Customer Support Technician

[IntelSupport]

Hello Paul11

Thank you for waiting.

Please try/confirm the following settings on your system and OS:

·      What Power profile they have for ESXi when Turbo is not showing up?  the options usually are – High Performance / Balanced / Low Power / Custom

·      Please check for a BIOS option (or ask their OEM for help in locating the BIOS option) to disable Intel® Speed Shift Technology and set P state control to some sort of OS control with Legacy P states. Then, please set ESXi to “Balanced Mode” in the Power profile for the OS and see if any behavior changes? 

Hope this helps.

Regards,

Leonardo C.

Intel Customer Support Technician

[IntelSupport]

Hello Paul11

I am checking on your thread to know if need further assistance with this request.

Regards,

Leonardo C.

Intel Customer Support Technician

[AdrianM_Intel]

Hello Paul11,

Thank you for your patience.

Disabling cores is really up to how the system BIOS was designed by their system manufacturer (OEM). It is not an Intel requirement. It is up to the OEMs on how they want to control this in the BIOS.

Our recommendation is to let Legacy P states be controlled by the OS (operating system) and to do that is to disable Intel(R) Speed Shift Technology in the BIOS (if that option is made visible by the system manufacturer in the BIOS) and then set ESXi to “Balanced Mode” in the Power profile for the OS. Then check if they are able to get the higher Turbo Boost frequency.

We would also like to know what Power profile you have for ESXi when Turbo is not showing up – the options usually are – High Performance / Balanced / Low Power / Custom.

Regards,

Adrian M.

Intel Customer Support Technician