Stop stats collection on container exit

Signed-off-by: Alexander Morozov <lk4d4@docker.com>

event.go

@@ -22,7 +22,8 @@ const (
 	CreateCheckpointEventType EventType = "createCheckpoint"
 	DeleteCheckpointEventType EventType = "deleteCheckpoint"
 	StatsEventType            EventType = "events"
-	UnsubscribeStatsEventType EventType = "unsubscribeEvents"
+	UnsubscribeStatsEventType EventType = "unsubscribeStats"
+	StopStatsEventType        EventType = "stopStats"
 	OOMEventType              EventType = "oom"
 )
 

exit.go

@@ -32,6 +32,10 @@ func (h *ExitEvent) Handle(e *Event) error {
 	ne.Pid = e.Pid
 	ne.Status = e.Status
 	h.s.SendEvent(ne)
+
+	stopCollect := NewEvent(StopStatsEventType)
+	stopCollect.ID = container.ID()
+	h.s.SendEvent(stopCollect)
 	return nil
 }
 

stats.go

@@ -26,6 +26,10 @@ type UnsubscribeStatsEvent struct {
 	s *Supervisor
 }
 
+type StopStatsEvent struct {
+	s *Supervisor
+}
+
 func (h *StatsEvent) Handle(e *Event) error {
 	i, ok := h.s.containers[e.ID]
 	if !ok {
@@ -43,3 +47,12 @@ func (h *UnsubscribeStatsEvent) Handle(e *Event) error {
 	h.s.statsCollector.unsubscribe(i.container, e.Stats)
 	return nil
 }
+
+func (h *StopStatsEvent) Handle(e *Event) error {
+	i, ok := h.s.containers[e.ID]
+	if !ok {
+		return ErrContainerNotFound
+	}
+	h.s.statsCollector.stopCollection(i.container)
+	return nil
+}

supervisor.go

@@ -58,6 +58,7 @@ func NewSupervisor(id, stateDir string, tasks chan *StartTask, oom bool) (*Super
 		DeleteCheckpointEventType: &DeleteCheckpointEvent{s},
 		StatsEventType:            &StatsEvent{s},
 		UnsubscribeStatsEventType: &UnsubscribeStatsEvent{s},
+		StopStatsEventType:        &StopStatsEvent{s},
 	}
 	// start the container workers for concurrent container starts
 	return s, nil