[SOLVED] Oversubscription/overcommit vcpu

[rian81]

Hi

Is there a way how to set oversubs/overcommit vcpu on proxmox, for example if we have 32 core physical cpu and want to set 96 vcpu at pve node. So we can limit if create vm and the vcpu setting more than allowed will failed.

Thanks

 

[LnxBil]

No, currently not. You need to do that manually. Why do you want to limit it? Normally overcommiting is not a problem in a controlled environment.

 

[rian81]

Because vm not spread balance on each node pve cluster. My team when create vm almost do at node1. The purpose is for warning when the vcpu has reach the cpu limit. How to do it manually?

 

[LnxBil]

Because vm not spread balance on each node pve cluster. My team when create vm almost do at node1. The purpose is for warning when the vcpu has reach the cpu limit.

Good point, but a better metric would be the load, so that you check what acutally is used.

How to do it manually?

Create the VM always on the node with the least used node. It is shown in the node selection dropdown menu:



For a more automatic approach or warnings, you need to monitor the CPU usage of all your VMs, e.g. with an external metrics server and define alarming if there are VMs that behave "out-of-previous-behavior". This is a bit more work, yet you would need to do that on all hypervisors and this is the only thing that would actually be worth investing (at least in my book, please try to prove me wrong).