Intermitent crash when switching scene with LoadLevelAsync with Unity 5.2.0f3 and 5.2.1f1

Hi,

I recently updated my project to Unity 5.2.0f3 (from 5.1.3). Everything was fine but I soon discovered I had intermittent crashes when switching scene with LoadLevelAsync.

The crash were not happening in 5.1.3 and it can strike in both Unity Editor and Standalone build. I don't know if it's project specific and that is why I'm posting here.

At least it seems to be scene specific as I have 2 scenes in my current project:
- Level 0 is the main menu,
- Level 1 is the main game scene.
The crash happens when switching from Level 1 to Level 0 only, but not everytimes.

I'm attaching an output log, but despite the fact I've enabled development build and script debugging I don't have any clue exept the stack trace... Otherwise it seems it's crashing when unloading unused serialized files.

Has anyone noticed the same thing ?

 

Hmm... I have had some crashes with my build during scene load. I'm using LoadLevelAsync too.
The crashes have happened with another machine, but not with the one I'm using for development.
Unfortunately this all I know about this right now.

 

Thank you for the feedback!
I'm experimenting the crashes on several machines on my side.

 

Yesterday I updated to Unity 5.2.1f1 and I get the same intermittent crashes when it's unloading serialized files...
Would be great to have someone from UT to shed lights on this if possible.

 

Anyone ?

Still get the same anoying crashes during serialized files unload:

Code (csharp):

1.  
2. Unloading 3 Unused Serialized files (Serialized files now loaded: 0)
3. Crash!!!
4. ...
5.  

I'd like to know, what does this means ?

 

Still happen with Unity 5.2.1p2...

 

I am also experiencing this issue on 5.2.1p1.

 

@karl.jones Not yet it seems... My project is around 20GB so it's a bit too much to send as a repro case. I'm trying to get a repro case from the ground up but once again it seems to be scene specific...

 

same problem with me. Its intermitant

 

I'm currently doing quite big changes in my open world scene as I want to stream it. I disabled a script that was used by some gameObject to translate their messages printed on screen and it seems the crash has gone.
I'll investigate further to see if I can find the culprit.

 

We had this before Unity 5.2 landed. Link here. It had to do with IL2CPP running out of file handles (I think) - but should be fixed now. I havent seen the bug since 5.2 at least. Which platform are you on? our project was iOS.

 

On my side I'm on Windows 7 64bit. I don't think it's the same bug, the one I'm getting appears when unloading serialized files.
The crashes appeared on 5.2 on our side.

 

I just moved back to 5.1.3 and don't have an issue anymore.

 

Has there been a fix for this yet?

 

5.2.2 here, 100% while loading/unloading specific set of prefabs.
No info in the crash log;

 

I see @karl.jones is here helping, but have you tried loading an empty scene before your next scene? It clears the cache and is very useful

 

I'm experiencing similar issues, in my case the editor or player won't crash, sometimes it will start to consume 100% of CPU usage and RAM and freezes the whole system. In my knowledge there's no way for us to use 100% of the CPU resource in our c# code unless we start some custom threads, which isn't the case. I tried to troubleshoot the problem and investigated my code and couldn't find anything.

I'm not able to reproduce the situation everytime, it happens like once every 10 Scenes, I'll submit a bugreport if I find a way to reproduce it.

Ps. I'm using 5.2.2

 

On my side I do no longer have the problem, this is very strange... Maybe a fact that I cleared the GI cache and wiped baked data to bake it again, I'm not sure.

 

I would definitely suggest loading an empty scene in between scenes. This releases the cache/memory before loading the next scene.

 

Usually what we do is loading an empty scene (not actually empty since it contains a "loading" animated sprite, but whatever), call the Garbage Collector to free the memory and then load the next scene asyncronously while the loading icon is shown.

That's the most convenient way to proceed, I presume.

 

In my case, there is no scene. I'm loading/unloading prefabs using Resources.

 

Sadly, it's not possible to send them over. The issue of developing for a third-party who want to keep everything behind closed door. Right now we reverted to 5.1 because we ship next week.

 

Okay so i was having the same problem but i did a little workaround with bools, what crashed me was everytime i put the Scenemanager.SceneUnload on a void OnTriggerExit it crashed everything, build and editor.

This is probably good for people looking for a World of Warcraft style level loading All it needs is networking

Here's my workaround:

Code (CSharp):

1. using UnityEngine;
2. using System.Collections;
3. using UnityEngine.SceneManagement;
4.  
5. public class InteriorLoad : MonoBehaviour {
6.  
7.     [Tooltip("Name of the scene you desire to load.")]
8.     public string SceneToLoad;
9.     private bool interiorIsLoaded;
10.     private bool unlodingInterior;
11.  
12.     void Start()
13.     {
14.         interiorIsLoaded = false;
15.         unlodingInterior = false;
16.     }
17.  
18.     void Update()
19.     {
20.         if (unlodingInterior)
21.         {
22.             SceneManager.UnloadScene(SceneToLoad);
23.             unlodingInterior = false;
24.             interiorIsLoaded = false;
25.         }
26.     }
27.  
28.     void OnTriggerEnter(Collider other)
29.     {
30.         if (interiorIsLoaded == false)
31.         {
32.             SceneManager.LoadScene(SceneToLoad, LoadSceneMode.Additive);
33.             interiorIsLoaded = true;
34.         }
35.         else
36.         {
37.             return;
38.         }
39.     }
40.     void OnTriggerExit()
41.     {
42.         if (interiorIsLoaded == true && unlodingInterior == false)
43.         {
44.             unlodingInterior = true;
45.         }
46.         else
47.         {
48.             return;
49.         }
50.     }
51. }

 

Also noticed that asking Unity to load the same thing twice in the same frame make it goes insane. For a few dozen frames, it generates ton of garbages.

However, if I call something only once per frame, it's all fine.

 

Nevermind... We had a "Resources.UnloadUnusedAsset" that was taking 50ms and for some reason making everything - physic included - choking like someone who is smoking a car tailpipe.

To be honest, resources unloading is still a very obscure system that you're never totally sure something was properly unloaded, and that you somehow can unload from 3-4 different way, which doesn't all work for each resource type.