Issues with hot plug processors

[damo2929]

hi guys
search didn't bring me a result for this but am having issues with ram and CPU hot plug. in version 9.1.4.

the proxmox UI doesn't apply them, despite hot plug being enabled, it doesn't appear to work on any VM regardless of guest OS.
can somebody tell me why this isn't applying as per the documentation .

 

[apoyen]

Hello,
It's because your using this functionnality the wrong way.

You have to set your maximal number of vcpu you want on your vm, this value is the total core (socket * cores). You need to restart to set this value.
Next you activate the advanced options and set the Vcpu value that will correspond to your desired vcpu count you want without restarting.

Then you can modify your Vcpu value that can't exceed the total core value.

 

[apoyen]

In fact you can't modify socket or cores value without rebooting. Only the Vcpu value can be modified without rebooting when you want to do CPU Hotplug .