I know I could test this, but I don't have the time right now to setup pristine test conditions to learn something that should be in documented form - and that I cannot find in an authoritative form.
I am thinking that the CPU% consumed on a VM is relative to the total CPU allotted to the VM and that spare CPU cycles on the host are allotted to all running VMs in a host equally.
So given 2 VMs on a host, where VM1 is consuming 50%
of the host CPU capacity and VM2 is consuming 10%
of the host CPU capacity. So 40%
CPU capacity is available and divided equally into the running VMs.
VM1 sees
a CPU potentiality 70%
of the total host CPU (50%
actual CPU consumed + 20%
-or half- of the spare cycles). So VM1 records CPU consumption of 71.42%
(50%
actual / 70%
allotted total * 100 = 71.42%
and 28%
CPU free.
VM2 sees
a CPU potentiality of 30%
of the total host CPU (10%
actual CPU consumed + 20%
-or the other half- of the spare cycles). So, VM2 records CPU consumption of 33.333%
and 66.666%
free.
Stopping any one of the VMs should immediately increase the spare CPU available to the other and this should show up as a drop in the CPU consumption of the other.
True or False? If False, what don't I understand?