How can calculate vCPU / Core in vsan sizer

[baber]

As I know there are two options in vsan sizer :

vCPU / Core:

vCPU / VM:

I know vCPU / VM means how many vcpus your vm will e used or you will be assign

now would you say what does vCPU / Core .?   how can calculate this ?

for example in my cluste I have 10 server with follow info :

Processor sockets     4

Processor cores per socket     28

BR

[TheBobkin]

Hello baber ,

vCPU per core is essentially the over-subscription ratio, e.g. how many vCPUs are assigned to VMs Vs Cores available - going beyond 3:1 is generally touted as not ideal.

Bob

[baber]

Thanks.

1- Is that your means that is better define 3 vcpu for each cpu core ?

2- on the other hand according to previous info about my esxi hosts , I have selected  "For availability, distribute a more even number of virtual machines across hosts."

and Over-commitment ratio = 3

Is that ok ?

[TheBobkin]

Hello baber​,

"1- Is that your means that is better define 3 vcpu for each cpu core ?"

Yes.

"2- on the other hand according to previous info about my esxi hosts , I have selected  "For availability, distribute a more even number of virtual machines across hosts."

and Over-commitment ratio = 3

Is that ok ?"

This is basically a DRS setting that will aim to limit VM placement on hosts in accordance with best practices of aiming to have vCPU:core over-commitment ratio <4 (e.g. 3:1 ratio).

Bob