Hello,
Welcome to our community,
It seems that your VMs are CPU-Constraints and the VM may be have an issue in using resources and that can be examined from Guest-OS tools
Or may be the vm is limited in the amount of resources given from the host.
I found for you good article about CPU ready http://www.opvizor.com/blog/the-good-the-bad-and-the-ugly-about-vm-cpu-ready/