The hidden columns "CPU" and "Memory" in the OCPvm table can be clicked to perform a sort action, but that results in a "undefined" query param int the API request to backend

[...]filter[resolution]=monthly&filter[time_scope_units]=month&filter[time_scope_value]=-1&limit=10&offset=0&order_by[undefined]=asc

Which returns a 400 bad request so the UI will display unavailable

CPU and memory sorting should use request_cpu or request_memory query params