ANR in com.unity3d.player.UnityPlayer.updateDisplayInternal

Hi I get a lot of ANR related to com.unity3d.player.UnityPlayer.updateDisplayInternal.
Unity 2019.4.25f1

The common flow is :
.....App Stoped/App Paused
...
-> com.unity3d.player.UnityPlayer$21.surfaceDestroyed
...
-> com.unity3d.player.UnityPlayer.updateDisplayInternal
-> java.util.concurrent.Semaphore.tryAcquire

Here is more detailed log(I use ANR watchdog to get it):

Code (CSharp):

1. sun.misc.Unsafe.park (Unsafe.java)
2. java.util.concurrent.locks.LockSupport.parkNanos (LockSupport.java:230)
3. java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedNanos (AbstractQueuedSynchronizer.java:1063)
4. java.util.concurrent.locks.AbstractQueuedSynchronizer.tryAcquireSharedNanos (AbstractQueuedSynchronizer.java:1358)
5. java.util.concurrent.Semaphore.tryAcquire (Semaphore.java:415)
6. com.unity3d.player.UnityPlayer.updateDisplayInternal (Unknown Source:54)
7. com.unity3d.player.UnityPlayer.updateGLDisplay (Unknown Source:5)
8. com.unity3d.player.UnityPlayer.access$1100
9. com.unity3d.player.UnityPlayer$21.surfaceDestroyed (Unknown Source:4)
10. android.view.SurfaceView.updateSurface (SurfaceView.java:879)
11. android.view.SurfaceView.windowStopped (SurfaceView.java:315)
12. android.view.ViewRootImpl.setWindowStopped (ViewRootImpl.java:1977)
13. android.view.WindowManagerGlobal.setStoppedState (WindowManagerGlobal.java:709)
14. android.app.Activity.performStop (Activity.java:8181)
15. android.app.ActivityThread.callActivityOnStop (ActivityThread.java:4987)
16. android.app.ActivityThread.handleSleeping (ActivityThread.java:5124)
17. android.app.ActivityThread.access$2500 (ActivityThread.java:270)
18. android.app.ActivityThread$H.handleMessage (ActivityThread.java:2149)
19. android.os.Handler.dispatchMessage (Handler.java:107)
20. android.os.Looper.loop (Looper.java:237)
21. android.app.ActivityThread.main (ActivityThread.java:7948)
22. java.lang.reflect.Method.invoke (Method.java)
23. com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:493)
24. com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1075)

And here is function UnityPlayer.updateDisplayInternal

Code (CSharp):

1. private boolean updateDisplayInternal(final int var1, final Surface var2) {
2.         if (n.c() && this.mState.e()) {
3.             final Semaphore var3 = new Semaphore(0);
4.             Runnable var4 = new Runnable() {
5.                 public final void run() {
6.                     UnityPlayer.this.nativeRecreateGfxState(var1, var2);
7.                     var3.release();
8.                 }
9.             };
10.             if (var1 == 0) {
11.                 if (var2 == null) {
12.                     this.m_MainThread.b(var4);
13.                 } else {
14.                     this.m_MainThread.c(var4);
15.                 }
16.             } else {
17.                 var4.run();
18.             }
19.  
20.             if (var2 == null && var1 == 0) {
21.                 try {
22.                     if (!var3.tryAcquire(4L, TimeUnit.SECONDS)) {
23.                         g.Log(5, "Timeout while trying detaching primary window.");
24.                     }
25.                 } catch (InterruptedException var5) {
26.                     g.Log(5, "UI thread got interrupted while trying to detach the primary window from the Unity Engine.");
27.                 }
28.             }
29.  
30.             return true;
31.         } else {
32.             return false;
33.         }
34.     }

Do anyone have similar problem or any idea to overcome it?
Thank you.

 

Thank you Tomas!! I'll try it.

I can't reproduce on my end too. It's happened on wide range of devices, android versions.
The only notable info is 76% of this ANR is when app in background.

 

Hi Tomas, Crashlytic has that info.

 

Code (JavaScript):

1.     public  void pause() {
2.         Log.i(TAG, "pause: start--"+isShow);
3.         if(true){
4.             super.pause();
5.             for (int i = 0; i < getChildCount(); i++) {
6.                 final View child =getChildAt(i);
7.                 if(null!=child){
8.                     Log.i(TAG,"pause---"+child.toString());
9.                     post(new Runnable() {
10.                         @Override
11.                         public void run() {
12.                             child.setVisibility(View.GONE);
13.                         }
14.                     });
15.  
16.                 }
17.  
18.             }
19.             windowFocusChanged(false);
20.             isShow=false;
21.         }
22.         Log.i(TAG, "pause: end");
23.     }

Is there a solution to this problem?I modified the pasue () of unityplay and called pause (), which caused the same problem.

 

Unfortunately, I didn't find any. Tried to remove all code in OnDisable, OnDestroy, OnApplicationPause, OnApplicationQuit. But the ANR still high.

 

same issue

 

Hi , any update on this ?

 

@Tomas1856 The majority of our ANR start with `com.unity3d.player.UnityPlayer.surfaceDestroyed` too. My guess is UnityPlayer blocks 'main' thread waiting on some semaphore for something queued on to 'UnityMain' or other thread. I have no access to sources to check this hypothesis and I have no clues how to resolve that ANR.
Can you help with investigation, please?

 

up

 

Up top, i have same issue

 

up

Code (CSharp):

1. main (timed waiting): tid=1 systid=16340
2.        at sun.misc.Unsafe.park(Native method)
3.        at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:230)
4.        at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedNanos(AbstractQueuedSynchronizer.java:1063)
5.        at java.util.concurrent.locks.AbstractQueuedSynchronizer.tryAcquireSharedNanos(AbstractQueuedSynchronizer.java:1358)
6.        at java.util.concurrent.Semaphore.tryAcquire(Semaphore.java:415)
7.        at com.unity3d.player.UnityPlayer.updateDisplayInternal(unavailable)
8.        at com.unity3d.player.UnityPlayer.updateGLDisplay(unavailable)
9.        at com.unity3d.player.UnityPlayer.access$1100(unavailable)
10.        at com.unity3d.player.UnityPlayer$19.surfaceDestroyed(unavailable)
11.        at android.view.SurfaceView.notifySurfaceDestroyed(SurfaceView.java:1943)
12.        at android.view.SurfaceView.updateSurface(SurfaceView.java:1239)
13.        at android.view.SurfaceView.setWindowStopped(SurfaceView.java:291)
14.        at android.view.SurfaceView.surfaceDestroyed(SurfaceView.java:1767)
15.        at android.view.ViewRootImpl.notifySurfaceDestroyed(ViewRootImpl.java:1891)
16.        at android.view.ViewRootImpl.setWindowStopped(ViewRootImpl.java:1826)
17.        at android.view.WindowManagerGlobal.setStoppedState(WindowManagerGlobal.java:700)
18.        at android.app.Activity.performStop(Activity.java:8398)
19.        at android.app.ActivityThread.callActivityOnStop(ActivityThread.java:4981)
20.        at android.app.ActivityThread.performStopActivityInner(ActivityThread.java:4960)
21.        at android.app.ActivityThread.handleStopActivity(ActivityThread.java:5034)
22.        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:233)
23.        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:201)
24.        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:173)
25.        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97)
26.        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2135)
27.        at android.os.Handler.dispatchMessage(Handler.java:106)
28.        at android.os.Looper.loop(Looper.java:236)
29.        at android.app.ActivityThread.main(ActivityThread.java:8059)
30.        at java.lang.reflect.Method.invoke(Native method)
31.        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:656)
32.        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:967)

 

I can't reproduce it locally, this is from Crashlytics.

This is on Xiaomi Redmi Note 10 Pro

 

Yes it crashes because

Activity.onPause

in

main

(as I can see from crash logs) is synchronized with

UnityMain

thread via a semaphore lock. Thus the

main

can be blocked by heavy operation in

UnityMain

thread. In our case it is a loading.

2020.3.0f1

 

1. We do loading at

Unity Main

. Currently it is a heavy synchronous routine but it is a script running at `Unity Main` and technically it must not cause an ANR.

2. Player minimizes his app and it goes to background.

UnityPlayerActivity.onPause

is triggered by Android on the

main

thread.

3. Currently I believe that

UnityPlayerActivity.onPause

waits for

UnityMain

which is busy loading our files.

main

is blocked - ANR is fired. That's it.

 

Hey,
just letting you know that we are seeing this ANR also with 2020.3.17f1 in Google play vitals. Unfortunately we dont have local repro case either.

Top 5 offenders:
1. Motorola moto g(30)25 (Qualcomm SM6115)
16.2%

2. Redmi Note 10 Qualcomm SM6150
7.8%

3. Motorola moto g(9) 7.8%
Qualcomm SM6115

4. Motorola moto g(9) power
7.1%
Qualcomm SM6115

5. Lenovo K13 Note
5.8%
Qualcomm SM4350

I tried this script in different scenes and couldnt get app to hang or crash.

 

Has anyone resolved this issue?

 

up

Code (CSharp):

1. main (timed waiting): tid=1 systid=2430
2.        at sun.misc.Unsafe.park(Native method)
3.        at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:230)
4.        at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedNanos(AbstractQueuedSynchronizer.java:1063)
5.        at java.util.concurrent.locks.AbstractQueuedSynchronizer.tryAcquireSharedNanos(AbstractQueuedSynchronizer.java:1358)
6.        at java.util.concurrent.Semaphore.tryAcquire(Semaphore.java:415)
7.        at com.unity3d.player.UnityPlayer.updateDisplayInternal(unavailable)
8.        at com.unity3d.player.UnityPlayer.updateGLDisplay(unavailable)
9.        at com.unity3d.player.UnityPlayer.access$1100(unavailable)
10.        at com.unity3d.player.UnityPlayer$19.surfaceDestroyed(unavailable)
11.        at android.view.SurfaceView.notifySurfaceDestroyed(SurfaceView.java:1830)
12.        at android.view.SurfaceView.updateSurface(SurfaceView.java:1126)
13.        at android.view.SurfaceView.setWindowStopped(SurfaceView.java:278)
14.        at android.view.SurfaceView.surfaceDestroyed(SurfaceView.java:1654)
15.        at android.view.ViewRootImpl.notifySurfaceDestroyed(ViewRootImpl.java:1880)
16.        at android.view.ViewRootImpl.setWindowStopped(ViewRootImpl.java:1836)
17.        at android.view.WindowManagerGlobal.setStoppedState(WindowManagerGlobal.java:694)
18.        at android.app.Activity.performStop(Activity.java:8292)
19.        at android.app.ActivityThread.callActivityOnStop(ActivityThread.java:4915)
20.        at android.app.ActivityThread.performStopActivityInner(ActivityThread.java:4894)
21.        at android.app.ActivityThread.handleStopActivity(ActivityThread.java:4968)
22.        at android.app.servertransaction.StopActivityItem.execute(StopActivityItem.java:40)
23.        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:176)
24.        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:97)
25.        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2115)
26.        at android.os.Handler.dispatchMessage(Handler.java:106)
27.        at android.os.Looper.loop(Looper.java:250)
28.        at android.app.ActivityThread.main(ActivityThread.java:7755)
29.        at java.lang.reflect.Method.invoke(Native method)
30.        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:592)
31.        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:958)

Also happening in background based on firebase

 

@Tomas1856 any news on how to fix this ANR? what is causing it?

 

Hey @Thomas1856,

We noticed that our game was getting a large amount of these issues relating to the unity3d.player.UnityPlayer.updateDisplayInternal showing up on our Google Play Developer Console for phones like the Motorola devices and the similar lists posted above. We went out and purchased one of the affected devices on Android 11, and was able to reproduce the ANR pretty reliably. At least in our case, it was due to the Application.Quit() function being used on these devices. The game would go into the background and look like it had quit correctly, but then the player was prompted with the "App not responding" popup which is triggering the ANR to show up on the Google Play Developer Console.

We are using Unity 2020.3.26f1, and we have temporarily removed the quit functionality from the game only on those devices, and our ANR rate has dropped considerably.

 

My project already use Screen.sleepTimeout = SleepTimeout.NeverSleep, but still have ANR problem in
com.unity3d.player.UnityPlayer.updateDisplayInternal. So except remove Application.Quit() , Any further solution of this problem?

 

Hilarious, I've seen this ANR for months on the dashboard and never considered it to be coming from the Application.Quit call. Could you tell me what specific device this repros on that you purchased?

 

Hey @livingtarget,

We purchased a Motorola G9 and upgraded it to Android 11, which seemed to be the version which was causing the most issues. The Application.Quit functionality has been a bit problematic in the past, so we did suspect it was a possible cause.

For reference, we released an update in the past week which removed the Quit button on Motorola G, Motorola E and Motorola One devices running Android 11 or higher, which were some of the worst offenders for this issue. We are still seeing this error in our dashboard, but is only for a small subset of other devices. Our ANR rate has almost halved compared to the previous week.

 

@hba_infinity I took a bit more hard line approach and excluded all Motorola users and rolled it out to 50% of the users and found exactly what you told us. Basically removing the Application.Quit() caused this ANR in Firebase to go from 14 ANRs down to zero after like 5 or so days.

So I mean that points almost exclusively to Application.Quit() causing an ANR for these devices when it probably shouldn't. I mean there is still a possibility we are doing too much in OnDisable() OnApplicationQuit(), but generally speaking I already tried to improve that and don't really know if there's too much more to optimise let alone hard to debug outside the editor.

I mean it's almost impossible to create a repro for a case like this to submit to Unity though, so I don't know what they are going to do about it if anything.

 

Hey guys! Here is my analysis and the solution we did implemented.

The line

java.util.concurrent.Semaphore.tryAcquire()

in the call-stack indicates that `main` thread was waiting on a semaphore when ANR was triggered.

But in the Unity code (you can check with Java decompiler) it is timed awaiting with 4 seconds timeout:

Code (CSharp):

1. if (!semaphore.tryAcquire(4L, TimeUnit.SECONDS))
2.     ...
3.  

This 4 seconds timeout is Unity's protection against triggering an ANR because of main thread waiting on a semaphore for too long. But we still get this ANR

Basically this ANR means that your Unity code takes at least 4 seconds PLUS there is some other code which executes on your

Activity.onStop()

because ANRs are triggered after 5 seconds. This can be any third-party SDK implementing

Application.ActivityLifecycleCallbacks

or something like that.

In my case players were quitting a heavy scene and a lot of stuff was happening in

OnApplicationPause()

,

OnApplicationQuit()

,

OnDisable()

and

OnDestroy()

. Please note that all of these happen during a single frame so you can easily spend 4 seconds on some older device if you are qutting from the gameplay scene.

What I did was when a user confirms that he or she wishes to quit the game:
1. First, I do unload current heavy scene (switching to an empty scene). This does all heavy scene unloading as usual (we are not stopping the Android Activity yet)
2. Only then I do call

Application.Quit()

and this wont take much time because we are on an empty scene now. But watch your DontDestroyOnLoads.

And watch your third party SDKs. Keep only the bare minimum that you need. Most likely you cannot influence how they use

Application.ActivityLifecycleCallbacks

.

 

i removed Application.Quit() but anr still remains high

 

I saw this go down from 1.23% all the way down to 0.93% over 30 days. ANR rates are notorious in spiking at random intervals so the only way to check is to leave it up over a longer period of time.

Also make sure you are actually seeing this exact same one. It should say ActivityThread.handleStopActivity in the stack trace.

This is how I prevent our quit dialog box to show on Motorola devices. It's a pretty broad catch.

Code (CSharp):

1. #if UNITY_ANDROID
2.         string deviceModel = SystemInfo.deviceModel;
3.         if (!string.IsNullOrEmpty(deviceModel))
4.         {
5.             string deviceModelLower = deviceModel.ToLower();
6.  
7.             // just ignore all motorola devices to see if it makes a difference
8.             if (deviceModelLower.Contains("moto"))
9.             {
10.                 // ignore calling Application.Quit() on certain devices
11.                 return;
12.             }
13.         }
14. #endif

Also tried the unloading of the scene with this code and I'm still monitoring the results as it's not been live for a long time yet, but it seemed to have dropped to 0.76% in the last week.

Code (CSharp):

1. protected static void QuitApplication()
2.     {
3.         if (IsDelayedQuitEnabled())
4.         {
5.             Debug.Log("Delayed Quit");
6.  
7.             // ignore if already flagged as shutting down
8.             if (GameClient.IsShuttingDown())
9.                 return;
10.  
11.             // grab the current scene so we can unload it
12.             Scene currentScene = SceneManager.GetActiveScene();
13.  
14.             // create an empty scene and make active
15.             Scene scene = SceneManager.CreateScene("quit", new CreateSceneParameters(LocalPhysicsMode.None));
16.             SceneManager.SetActiveScene(scene);
17.  
18.             // quit after unloading the scene
19.             AsyncOperation asyncOperation = SceneManager.UnloadSceneAsync(currentScene);
20.             asyncOperation.completed += (AsyncOperation op) => { Application.Quit(); };
21.  
22.             // try to dispose of some things, this could be moved before but here in case it throws exceptions
23.             PreDispose();
24.         }
25.         else
26.         {
27.             Application.Quit();
28.         }
29.     }

So this code is basically unloading the current active scene and hopefully cutting some time off the time it takes to quit the game. This does however add a delay where the game is still active before you are quitting, so it's a trade off and you may want to visually indicate that the game is actually going down.

I would recommend to test this code, use it at your own risk and only apply this if you know for certain that you have this problem and for sure only target Android devices.

 

Wow, nice idea. Thank

 

Code (CSharp):

1. public class GameClientServices {
2.         public void Quit() {
3. #if UNITY_ANDROID
4.             try {
5.                 PlayerPrefs.Save();
6.                 new AndroidJavaClass("java.lang.System").CallStatic("exit", 0);
7.             } catch (Exception ex) {
8.                 Debug.LogError($"GameClientServices :: Quit has exception {ex}");
9.             }
10.  
11. #else
12.             UnityEngine.Application.Quit();
13. #endif
14.         }

I've used code above to replace

Code (CSharp):

1. Application.Quit()

and it worked

 

I remove Application.Quit, unload heavy scene before quit the game but ANR still high.
Maybe ANR come from Ads medition, I use ironSource Sdk, admob adapter, vungle, unity, meta, adcolony, applovin

 

up, still facing this issue.

 

After add scene unload and after this Application.Quit, still facing this issue

 

We deferred quitting specifically on motorola and xiaomi devices and our ANR rates dropped significantly, from 300-400 per day down to maybe 60 per day.

What we did:
If it's a "motorola" or "xiaomi" (SystemInfo.deviceModel contains the substring),
- Show a placeholder (loading or Quitting UI)
- Synchronously load an empty scene (that will unload existing scenes)
- yield for one frame
- call Application.Quit();

The occurences aren't completely gone, but significantly enough to put us back into acceptable behaviour territory by a cozy margin.

 

2020.3.40f1 still reproducing this problem

Code (CSharp):

1. sun.misc.Unsafe.park (Unsafe.java)
2. java.util.concurrent.locks.LockSupport.parkNanos (LockSupport.java:230)
3. java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedNanos (AbstractQueuedSynchronizer.java:1063)
4. java.util.concurrent.locks.AbstractQueuedSynchronizer.tryAcquireSharedNanos (AbstractQueuedSynchronizer.java:1358)
5. java.util.concurrent.Semaphore.tryAcquire (Semaphore.java:415)
6. com.unity3d.player.UnityPlayer.updateDisplayInternal (UnityPlayer.java)
7. com.unity3d.player.UnityPlayer.updateGLDisplay (UnityPlayer.java)
8. com.unity3d.player.UnityPlayer.access$1100 (UnityPlayer.java)
9. com.unity3d.player.UnityPlayer$19.surfaceDestroyed (UnityPlayer.java)
10. android.view.SurfaceView.notifySurfaceDestroyed (SurfaceView.java:1942)
11. android.view.SurfaceView.updateSurface (SurfaceView.java:1238)
12. android.view.SurfaceView.setWindowStopped (SurfaceView.java:291)
13. android.view.SurfaceView.surfaceDestroyed (SurfaceView.java:1766)
14. android.view.ViewRootImpl.notifySurfaceDestroyed (ViewRootImpl.java:1900)
15. android.view.ViewRootImpl.setWindowStopped (ViewRootImpl.java:1835)
16. android.view.WindowManagerGlobal.setStoppedState (WindowManagerGlobal.java:710)
17. android.app.Activity.performStop (Activity.java:8378)
18. android.app.ActivityThread.callActivityOnStop (ActivityThread.java:5064)
19. android.app.ActivityThread.performStopActivityInner (ActivityThread.java:5043)
20. android.app.ActivityThread.handleStopActivity (ActivityThread.java:5117)
21. android.app.servertransaction.StopActivityItem.execute (StopActivityItem.java:40)
22. android.app.servertransaction.TransactionExecutor.executeLifecycleState (TransactionExecutor.java:176)
23. android.app.servertransaction.TransactionExecutor.execute (TransactionExecutor.java:97)
24. android.app.ActivityThread$H.handleMessage (ActivityThread.java:2172)
25. android.os.Handler.dispatchMessage (Handler.java:106)
26. android.os.Looper.loop (Looper.java:237)
27. android.app.ActivityThread.main (ActivityThread.java:8163)
28. java.lang.reflect.Method.invoke (Method.java)
29. com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run (RuntimeInit.java:656)
30. com.android.internal.os.ZygoteInit.main (ZygoteInit.java:967)

 

up

 

This is the main thread awaiting for unity thread to complete its execution on activity stop. The simplest reason could be some code does a lot of work in OnApplicationPause, OnApplicationFocus or OnApplicationQuit. Probably some synchronous I/O operation like a blocking web request.

 

We indeed do some I/O operations on Application quit.

Regarding the Application.Quit I've seen this:
https://docs.unity3d.com/2023.3/Documentation/Manual/android-quit.html

It says it's better to put the app in background on android than using the ApplicationQuit, "instead of Application.Quit. Activity.moveTaskToBack pauses the application and moves it to the background, which is closer to the standard Android application lifecycle than what Application.Quit"

Would make sense to change Application.Quit into this to avoid this kind of ANR's ?

Thanks!