[supervisor] fix ports forwarding hangs issue

components/supervisor/pkg/ports/exposed-ports.go

@@ -87,9 +87,9 @@ func NewGitpodExposedPorts(workspaceID string, instanceID string, workspaceUrl s
 		WorkspaceUrl:  workspaceUrl,
 		gitpodService: gitpodService,
 
-		// allow clients to submit 30 expose requests without blocking
-		requests:           make(chan *exposePortRequest, 30),
-		localExposedNotice: make(chan struct{}, 30),
+		// allow clients to submit 3000 expose requests without blocking
+		requests:           make(chan *exposePortRequest, 3000),
+		localExposedNotice: make(chan struct{}, 3000),
 	}
 }
 

components/supervisor/pkg/ports/ports.go

@@ -125,7 +125,7 @@ type managedPort struct {
 // Subscription is a Subscription to status updates
 type Subscription struct {
 	updates chan []*api.PortsStatus
-	Close   func() error
+	Close   func(lock bool) error
 }
 
 // Updates returns the updates channel
@@ -151,7 +151,7 @@ func (pm *Manager) Run(ctx context.Context, wg *sync.WaitGroup) {
 		pm.mu.Unlock()
 
 		for _, s := range subs {
-			_ = s.Close()
+			_ = s.Close(true)
 		}
 	}()
 	defer cancel()
@@ -324,7 +324,7 @@ func (pm *Manager) updateState(ctx context.Context, exposed []ExposedPort, serve
 		case sub.updates <- status:
 		case <-time.After(5 * time.Second):
 			log.Error("ports subscription droped out")
-			_ = sub.Close()
+			_ = sub.Close(false)
 		}
 	}
 }
@@ -766,20 +766,21 @@ func (pm *Manager) Subscribe() (*Subscription, error) {
 	}
 
 	if len(pm.subscriptions) > maxSubscriptions {
-		return nil, ErrTooManySubscriptions
+		return nil, fmt.Errorf("too many subscriptions: %d", len(pm.subscriptions))
+		// return nil, ErrTooManySubscriptions
 	}
 
 	sub := &Subscription{updates: make(chan []*api.PortsStatus, 5)}
 	var once sync.Once
-	sub.Close = func() error {
-		pm.mu.Lock()
-		defer pm.mu.Unlock()
-
+	sub.Close = func(lock bool) error {
+		if lock {
+			pm.mu.Lock()
+			defer pm.mu.Unlock()
+		}
 		once.Do(func() {
 			close(sub.updates)
 		})
 		delete(pm.subscriptions, sub)
-
 		return nil
 	}
 	pm.subscriptions[sub] = struct{}{}

components/supervisor/pkg/ports/ports_test.go

@@ -684,7 +684,7 @@ func TestPortsUpdateState(t *testing.T) {
 			}
 			go func() {
 				defer wg.Done()
-				defer sub.Close()
+				defer sub.Close(true)
 
 				for up := range sub.Updates() {
 					updts = append(updts, up)
@@ -864,8 +864,8 @@ func TestPortsConcurrentSubscribe(t *testing.T) {
 		}
 	}()
 
-	eg, _ := errgroup.WithContext(context.Background())
 	for i := 0; i < maxSubscriptions; i++ {
+		eg, _ := errgroup.WithContext(context.Background())
 		eg.Go(func() error {
 			for j := 0; j < subscribes; j++ {
 				sub, err := pm.Subscribe()
@@ -878,16 +878,17 @@ func TestPortsConcurrentSubscribe(t *testing.T) {
 				// update
 				case <-sub.Updates():
 				}
-				sub.Close()
+				sub.Close(true)
 			}
 			return nil
 		})
+		err := eg.Wait()
+		if err != nil {
+			t.Fatal(err)
+		}
+		time.Sleep(50 * time.Millisecond)
 	}
-	err := eg.Wait()
 	close(subscribing)
-	if err != nil {
-		t.Fatal(err)
-	}
 
 	wg.Wait()
 }

components/supervisor/pkg/supervisor/services.go

@@ -243,7 +243,7 @@ func (s *statusService) PortsStatus(req *api.PortsStatusRequest, srv api.StatusS
 	if err != nil {
 		return status.Error(codes.Internal, err.Error())
 	}
-	defer sub.Close()
+	defer sub.Close(true)
 
 	for {
 		select {