'Get the WAFL counters for calculating node utilization.'

def _get_node_utilization_wafl_counters(self, node_name):

    wafl_instance_uuids = self.zapi_client.get_performance_instance_uuids('wafl', node_name)
    wafl_counter_names = ['total_cp_msecs', 'cp_phase_times']
    wafl_counters = self.zapi_client.get_performance_counters('wafl', wafl_instance_uuids, wafl_counter_names)
    for counter in wafl_counters:
        if ('cp_phase_times' in counter):
            self._expand_performance_array('wafl', 'cp_phase_times', counter)
    return wafl_counters
