Do not try to use huge pages explicitly. Transparent huge pages are used automatically if they are available.
Kill libvirtd if checking the domains’ status is stuck for too long:
As of libvirt 3.9.0-14.el7_5, there is a bug that hungs libvirtd for unknown reasons. This renders the flexVDI platform unusable. If the agent suspects the libvirtd daemon to be hung, it kills it. Systemd automatically respawns it moments later and the problem is (temporally) solved.