code: func (engine *DockerStatsEngine) addAndStartStatsContainer(containerID string) {
  	engine.lock.Lock()
  	defer engine.lock.Unlock()
  	statsContainer, err := engine.addContainerUnsafe(containerID)
  	if err != nil {
  		seelog.Debugf("Adding container to stats watch list failed, container: %s, err: %v", containerID, err)
  		return
  	}
  
  	if engine.disableMetrics || statsContainer == nil {
  		return
  	}
  
  	statsContainer.StartStatsCollection()
  }
docs: // addAndStartStatsContainer add the container into stats engine and start collecting the container stats