I saw a page in the docs that says this results in "extremely poor performance, because the host machine can't process background tasks if all cores were assigned to the VM" (paraphrased).
source: Selecting the Number of Processors for a Virtual Machine
Why is this? I mean, doesn't the host also get to use all 4 of those cores? Or is VMware workstation set to realtime priority or something? If not then I can't see how the VM could actually block the host from using the cores. Can anyone explain this to me better?