Azure VM Core vs vCPU

azuremulti-corevcpuvirtual-machines

When comparing two different VM series in Azure, I see that one has Cores and the other one vCPUs. Keeping aside the number of Cores/CPUs, Memory and Processor Type (Intel Xeon E/Platinum etc), what is the advantage of one over the other? I understand that CPU can have multiple cores, but in Azure what is the difference between 4 vCPUs and 4 vCores?

G Series with Core
G Series with Core

D Series with vCPU
D Series with CPU

Best Answer

This is down to whether you get a real core or virtual core.

Older VM SKUs, and some specialised SKU's like H series have a 1 to 1 mapping between physical cores in the host machine and cores in the VM, so you are getting a real core dedicated to your VM, no hyperthreading.

Most recent SKU's, v3 and newer, are using hyperthreading and so the core allocated to your VM does not map 1 to 1 to a physical core in the host machine.