The resources allocated to a VM are locked with the VM as long as it runs. Assigning 2 cores to a VM running on a 2-core processor system means you're depriving your Mac of its processor resources. This certainly puts immense strain on your Mac hardware - a fact that won't change just because you assume it's alright to allocate just about all of the available cores to the VM.
No need to make pointless presumptions here. Moving away from your original question wasn't the intent; it was rather to provide answers along with stating the implications of the given setup. Hence the reason for asking you to change the setup so we could have observed how the numbers would look like this time.
Right to the answers then: If the VM has 2 cores allocated to it, multiply this number by 100%. So the VM's total consumption on Mac will equal 200%. Meaning, the VM's CPU consumption in Activity Monitor is normal if its consumption value is shown to be below 200% (it's again normal if the consumption value goes beyond 200% infrequently). Pls see this article for more details.
Last edited: Jun 22, 2017