Performance Impact Due to Mixed CPU Models in vSphere Cluster

[sreng channy]

I am reaching out to discuss a concern regarding the performance of VMs in our vCenter cluster. We currently have three servers in the cluster:

• 2 servers with Intel(R) Xeon(R) Gold 5317 CPU @ 3.00GHz
• 1 server with Intel(R) Xeon(R) Silver 4214R CPU @ 2.40GHz

Currently, the VMs are only running on the servers with the Intel(R) Xeon(R) Gold 5317 CPU @ 3.00GHz, and there is no migration or allocation to the server with the Intel(R) Xeon(R) Silver CPU. However, we are concerned that the presence of a server with a lower-spec CPU might still impact the overall performance of the virtual machine inside the cluster.

Thank you for your expertise, and I look forward to your response.

[Duncan Epping]

Well if you are capable of moving VMs between those hosts, then if the VM moves there could indeed be a performance impact as there's a significant speed difference. However, that is of course only the case when those workloads are pushing those CPUs to the max. We have plenty of customers mixing CPU families and different clock speeds without any issues. So if you are not experiencing any issues I would not be overly concerned at the moment.

[sreng channy]

Hi Duncan, 

So it means if the VM is still running on the hardware with CPU Intel(R) Xeon(R) Gold 5317 CPU @ 3.00GHz , the performance is based on the VMs stored in the hardware.
If we migration to he hardware with CPU Intel(R) Xeon(R) Silver 4214R CPU @ 2.40GH the performance is low based on the hardware system.