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joelau007
Contributor
Contributor
‎12-08-2013 02:52 AM

ESXi 5.5 power management C-states vs UEFI setting

Hi,

I sort of have to find an answer to this question before migrating from 5.1 to 5.5.

I have to prevent ESXi from using deep C-state C3. This is due to a design flaw in the IBM server hardware.

Therefore I have a setting in UEFI which limits to C2.

Now with ESXi 5.5, balanced power scheme will use deep C-states. How will this react with the UEFI setting ? Which takes priority, ESXi or UEFI setting ?

Regards.

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2 Replies
tomtom901
Commander
Commander
‎12-08-2013 05:47 AM

If you configure this in the BIOS / EUFI this will override anything the ESXi layer can do. To be extra sure, configure the hosts to use only High Performance power management (therefore limiting the options to either running or halted, not any other C states.

Reference document:

http://www.vmware.com/files/pdf/hpm-perf-vsphere5.pdf

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joelau007
Contributor
Contributor
‎12-08-2013 06:17 PM

5.5 version of the document,

http://www.vmware.com/files/pdf/techpaper/hpm-perf-vsphere55.pdf

I still want to use P-states so High performance is not what I'm after.

I can set it to Custom, and Power.UseCstate to turn off C-states, but this is still not the same as Balanced in 5.1 as I will lose the use of C1,C2.

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