How can I create a compute engine having reserved physical CPU(s)?

[EO_01]

Hi,

I'm trying to create and use Compute Engines so that I would be 100% sure that any of the underlying physical CPU(s) would be assigned to my non-preemptible VM.

I am running some very precise performance testing batches (using the getrusage API) and I need to ensure that my workloads are not only scheduled on the same CPU physical node but also using the same memory node.

I understand that when I get the output from "numactl -H" from GCP it's 'made-up' by GCP/KVM. Am I correct in my understanding?
Or is the output of "numactl -H" realistic of the underlying hardware my VM is using?

For example - if I pick a Ice Lake n2-standard-64 in Belgium, I reckon that the underlying physical CPUs are Intel® Xeon® Platinum 8373C Processor ( https://cloud.google.com/compute/docs/cpu-platforms ), and according to https://www.cpu-world.com/CPUs/Xeon/Intel-Xeon%208373C.html those have 36 cores/72 threads, which means that I should be getting a physical core to myself but then share other 4 cores/8 threads with somebody's else VM.

This is potentially bad because I can't quite pin my processes and the clock speed of some cores may vary depending on somebody's else workloads.

Am I wrong?

If so, how could I get my 'own' dedicated single CPU?
Should I setup a VM with 72 threads (or 144 to have 2 physical CPUs, but I don't think this is part of the offering)?

Many thanks!