NUMA questions

Spiros Pap

Well-Known Member
Aug 1, 2017
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Hi all,

There is an option to select NUMA when you configure a VM's CPU. While I know the basic NUMA concepts, I don't really understand what this checkbox does.
So, I have a few questions about it and an application that might benefit from enabling NUMA.
Starting from the App, I have a VM that does real time traffic analysis, using a pass-through network adapter. The adapter is placed on the PCIe bus of CPU0.

Can i use NUMA, to pindown the VM CPU and Memory on CPU0?

What does the NUMA checkbox in Proxmox actualy does? Does it keep all the VM CPU cores and memory on the same side? Do i have any control, which side that might be?

Is there a command to show me what physical resources (mem,cores) a VM uses?

Thank you,
Spiros
 
I cannot answer all your questions but have you checked out our documentation? There is a small section on NUMA https://pve.proxmox.com/pve-docs/pve-admin-guide.html#qm_virtual_machines_settings

To see how setting it will affect the starting of the VM you can run qm showcmd <VMID> --pretty once before and after enabling it.
Make sure though that your hardware is a NUMA architecture (footnote 29 in the documentation).