CPU tunning for Windows 11 VMs

[jasonwch]

I am going to setup a new mini PC (GMKTec K10 with i9-13900HK). This CPU have 6 P-core and 8 E-Core, 20 threads in total.

May I know if I assigned 1 socket and 18 Core (2 cores left for host) for my Win11 VM, PVE know how to schedule P-core to maximize VM performance? Is this scheduling automatic? Or I need to play with those pinning, affinity...etc? Because I want to keep it simple, so just want to know if PVE handle the scheduling well?

Thanks

 

[julyat]

unfortunately it’s not working like that

 

[jasonwch]

unfortunately it’s not working like that

Thanks for this, but can I know a bit more on your answer?

 

[julyat]

I’m not familiar with commercial hardware but if you want performance maybe you need to avoid using E-cores, just pin your vm with P-cores

 

[uzumo]

In a virtual machine, if you specify CPU affinity in addition to vCPU allocation, I believe cores not specified in the CPU affinity will not be used.

On PVE hosts, it is assumed that cores not specified in the virtual machine's CPU affinity (unassigned cores) will be used, but this point remains unclear.
*If cores specified in the virtual machine's CPU affinity are not being used, they will likely be scheduled and utilized by the PVE host.

During benchmark execution, (since clock speed cannot be used for identification, we rely on heat generation instead) we can determine that the cores are fixed based on the heat output.
*In the image, CPU affinity is configured to avoid using P-cores. Under these conditions, no increase in P-core heat generation is observed.
*A temperature increase attributable to heat generated by other cores is observed. The P-core clock does not increase.