I'm looking at repurposing a desktop PC as a new Proxmox server. My
hardware is ancient, I haven't been paying attention to recent trends.

I noticed one of the systems I was looking at had 2 power cores and 8 efficiency cores.

Does the type of CPU core matter to a hypervisor like Proxmox?



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Re: Efficiency cores?
By: poindexter FORTRAN to All on Thu Oct 23 2025 07:10 am

I'm looking at repurposing a desktop PC as a new Proxmox server. My
hardware is ancient, I haven't been paying attention to recent trends.

I noticed one of the systems I was looking at had 2 power cores and 8 efficiency cores.

Does the type of CPU core matter to a hypervisor like Proxmox?

As far as I know, no server-grade CPU has such a split between core types. That should tell you something.

Intel P/E cores are supported by the Linux kernel so that means if it is not included in the Proxmox kernel, you can include it anyway. Not that it matters.

In a typical production scenario your goal is to operate at 80% CPU load so you just disable powersaving non-sense. Under heavy load, the power efficient option is to crank cycles to the max so you do as much work as possible in the smallest timeframe. The real goal is to get as many operations per w.s as you can.

Under a homelab scenario you are very likely to have an underused CPU. If your CPU is commonly under 40% load then just disable Intel hybrid cores at the UEFI level, then have the Proxmox kernel put ALL CPU cores on powersave mode. I don't think you will notice the difference, but the computer will be generating less heat.


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Arelor wrote to poindexter FORTRAN <=-

Under a homelab scenario you are very likely to have an underused CPU.
If your CPU is commonly under 40% load then just disable Intel hybrid cores at the UEFI level, then have the Proxmox kernel put ALL CPU cores
on powersave mode. I don't think you will notice the difference, but
the computer will be generating less heat.

That would be a shame, since the system I was looking at had 2 power
cores and 8 efficiency cores. If I disabled the efficiency cores I'd end
up with the same cores/threads as my current 2c/4t system.

Interesting since Proxmox recognizes 4c/4t on my CPU but Intel's spec
sheet calls it 2c/4t.



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