Clarity on how CPU Pinning and CPU Isolation work

[Darryn]

Hi All,

 

I am struggling to understand how CPU Pinning and CPU Isolation work.

 

Can you please confirm if I am understanding this correctly?

 

If I have my set up like this:

 

 

 

Does that mean the Unraid OS is only able to use CPUs 0 and 1 (and not 2 and 3), the first 4 VMs will only use CPU 1 and the last VM will have exclusive use of CPUs 2 and 3?

 

Thank you for your help. 🙂

 

[testdasi]

Yes and No. In theory, yes all you did is correct.

 

However, heavy disk activities still have a chance of using the isolated cores.

There are mitigation that helps (see bug report below) but they don't resolve the issue.

 

I'm starting to think that it may not be an Unraid issue but a Linux issue as btrfs scrub shouldn't be Unraid specific.

 

Bug Report: