[Solved] A Native Collection has not been disposed, resulting in a memory leak.

So I have receiving none critical error at OnCreateManager () after NativeArray allocation.

A Native Collection has not been disposed, resulting in a memory leak C:\User\ .....

None critical, as code runs.

To simplyfy

Code (CSharp):

1. // for now
2. static public List <Nodes> octrees = new List <Nodes> () ;
3.  
4. public struct Nodes
5. {
6.     public int lastNodeIndex ;
7.     public NativeArray <Bounds> bounds ;
8.     ...
9. }
10.  
11. protected override void OnCreateManager (int capacity)
12. {
13. NodesData octree = new NodesData () ;
14. octree.bounds = new NativeArray<Bounds> ( 100, Allocator.Persistent ) ;
15. ...
16. // for now storing in the list
17. octrees.Add ( octree ) ;
18.  
19. // If I try add dispose, it throws error (see spoiler for full description)
20. // InvalidOperationException: The native container has been declared as [WriteOnly] in the job, but you are reading from it.
21. octree.a_bounds.Dispose () ;
22.  
23. }

Spoiler

InvalidOperationException: The native container has been declared as [WriteOnly] in the job, but you are reading from it.
Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle.CheckReadAndThrowNoEarlyOut (Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle handle) <0x1c7831c0 + 0x00052> in <f718fbf7147e402282fdacf37bdd8584>:0
Unity.Collections.NativeArray`1[T].CheckElementReadAccess (System.Int32 index) (at C:/buildslave/unity/build/Runtime/Export/NativeArray/NativeArray.cs:113)
Unity.Collections.NativeArray`1[T].get_Item (System.Int32 index) (at C:/buildslave/unity/build/Runtime/Export/NativeArray/NativeArray.cs:134)
ECS.Octree.Point.BoundingOctreeAddNodeSystem._Add2RootNode (System.Int32 i_octreeIndex, System.Int32 i_nodeIndex, ECS.Octree.EntityInstance entityInstance, ECS.Octree.Bounds entityBounds) (at Assets/Project/Scripts/Octree/Systems/BoundingOctreeAddNodeSystem.cs:455)
ECS.Octree.Point.BoundingOctreeAddNodeSystem._AddEntity (System.Int32 i_octreeIndex, ECS.Octree.EntityInstance entityInstance) (at Assets/Project/Scripts/Octree/Systems/BoundingOctreeAddNodeSystem.cs:418)
ECS.Octree.Point.BoundingOctreeAddNodeSystem+AddNode.Execute () (at Assets/Project/Scripts/Octree/Systems/BoundingOctreeAddNodeSystem.cs:268)
Unity.Jobs.IJobExtensions+JobStruct`1[T].Execute (T& data, System.IntPtr additionalPtr, System.IntPtr bufferRangePatchData, Unity.Jobs.LowLevel.Unsafe.JobRanges& ranges, System.Int32 jobIndex) (at C:/buildslave/unity/build/Runtime/Jobs/Managed/IJob.cs:30)

Without dispose it works. However it throws errors at initialization, then let code run.
What I am missing?
[ReadOnly] ?

Is the List an issue?

 

The dispose call has to be done when you close the application or have no more use for the bounds array in the octrees node list.

if you dispose it right away you will get errors whenever you try to use the NodesData since the array is disposed.

 

Ah ..
Silly me. Thx lot.

Added

Code (CSharp):

1. protected override void OnDestroyManager ( )
2. {
3. .. dispose calls
4. }

This solves the issue.
So error was actually from previous simulation. Makes sense.

 

I would like indicate one more thing upon that error message, since it came back, after migrating to latest Entities preview 11.

It is more feature request.

It would be nice, if such error ..

A Native Collection has not been disposed, resulting in a memory leak. It was allocated at C:\Users\...\AppData\Local\Unity\cache\packages\packages.unity.com\com.unity.collections@0.0.9-preview.3\Unity.Collections\NativeList.cs:24.

... could point into a script, where the error is generated. I got multiple scripts in project with native arrays and not sure, where the error is called from. Had no errors before upgrade, so now I need check manually every possible location, where dispose may be missing.

 

Most of them have some hints (# line of code) to allow track them down. Or even double click works.
But still having from to time, these which are hard to track down.

Anyway, looking forward to an update.
Thx

 

Hi Simon,

Do you know if there is any progress on this feature?

Thanks!

Pieter

 

With latest Entities 0.0.12 preview 20, error shows now the system *.cs file name and the job line.
This is big help already. Thx @simonm_unity
However, error do not indicates, which NativeArray may cause the problem.
So if you have more than one array, this may become tedious to find source of issue.

 

How do I enable the full stack trace on 2019.2.0a4? I get a bunch of "
A Native Collection has not been disposed, resulting in a memory leak. Enable Full StackTraces to get more details." without any traces, just that line. Already tried enabling it from the console menu and player settings, even disabled burst but still the same.

 

Any follow up from the above? I'm on 2019.1.0b4, can't see a way to turn it on... setting somewhere?

 

I don't seem to have that menu in 2019.1.0b4. I tried installing the jobs package (0.0.7) but it doesn't seem to compile on 2019.1.

 

That menu option comes with the Jobs package. Good luck finding the right combination of versions to make it compile. Wiping the shader and package cache does help sometimes.

 

Thanks; I was looking for this!

 

Taken from another thread:
https://forum.unity.com/threads/a-n...ry-leak-enable-full-stacktraces-to-ge.631198/

if you are looking for the option and you only see Burst inside the Jobs menu, then you have to go to the package manager and install the Entities package, that has a lot of dependencies and will make the rest of the options visible (at least with 2019.4).

After that you will see the Leak Detection options and the jobs debugger.

 

I don't think this is necessary anymore. With the latest burst, jobs and collections packages I get the options

 

I get

I believe this is related to PlayFab.

 

Yep. You're right. It's working now.

 

You're Right, I deleted Playfab in a copy of the Project and it fixed that issue.

 

I just upgraded my project from Unity 2019 to 2021, and now I'm seeing this error. My project doesn't use any burst/job features (that I know of). I didn't see the full stack trace option so I installed the com.unity.entities package as I've seen recommended on various threads. However, that package throws a bunch of compiler errors. Not sure what to do.

 

I don't see a version 0.51. 0.50 is the latest version that was released on March 16, 2022.
I saw another thread from about 2 years ago where someone said that they needed to improve the whole issue because it's silly to require a package to debug a core issue. Apparently that never happened?

 

What elliotc was trying to say is that u need to update the unity editor to 2020.3.30, anything lower won't work.
Entities 0.51 has not been released yet and there's no ETA.

I do agree on the frustration with unity versioning and the packages.

 

But I'm already using Unity 2021.2.16f1 (I just started using it). The issue never appeared in Unity 2020.3.7f1.

 

Yup, because 2021 is not supported yet. Only 2020.3.30 up to 2020.3.XX. nothing else (at least not officially).
I guess unity has a couple of big clients using latest 2020 and ECS cuz otherwise, this 0.50 release makes little sense.

 

@elliotc-unity
Ok... what should I do to deal with these errors in Unity 2021? I have a feeling they're coming from the Unity engine, because my code doesn't use any native collections. I can't tell where they're coming from without a full stack.

 

I think your packages repo is corrupted or something, your errors are related to ECS and burst, but if this screenshot you posted in the other thread is from the same project, you shouldn't have any of those packages installed.

 

Yes, it's the same project. What do you mean I shouldn't have any of those packages installed? Do you mean the ones listed that are actually installed? Or the burst one? Here's the contents of the manifest.json file:

{
"dependencies": {
"com.onesignal.unity.android": "3.0.0-beta.6",
"com.onesignal.unity.core": "3.0.0-beta.4",
"com.onesignal.unity.ios": "3.0.0-beta.6",
"com.unity.2d.animation": "7.0.4",
"com.unity.2d.psdimporter": "6.0.3",
"com.unity.2d.sprite": "1.0.0",
"com.unity.analytics": "3.6.12",
"com.unity.ide.rider": "3.0.12",
"com.unity.ide.visualstudio": "2.0.14",
"com.unity.ide.vscode": "1.2.5",
"com.unity.mobile.android-logcat": "1.2.3",
"com.unity.purchasing": "4.1.3",
"com.unity.test-framework": "1.1.31",
"com.unity.textmeshpro": "3.2.0-pre.3",
"com.unity.timeline": "1.6.4",
"com.unity.ugui": "1.0.0",
"com.unity.xr.legacyinputhelpers": "2.1.9",
"com.unity.modules.ai": "1.0.0",
"com.unity.modules.androidjni": "1.0.0",
"com.unity.modules.animation": "1.0.0",
"com.unity.modules.assetbundle": "1.0.0",
"com.unity.modules.audio": "1.0.0",
"com.unity.modules.cloth": "1.0.0",
"com.unity.modules.director": "1.0.0",
"com.unity.modules.imageconversion": "1.0.0",
"com.unity.modules.imgui": "1.0.0",
"com.unity.modules.jsonserialize": "1.0.0",
"com.unity.modules.particlesystem": "1.0.0",
"com.unity.modules.physics": "1.0.0",
"com.unity.modules.physics2d": "1.0.0",
"com.unity.modules.screencapture": "1.0.0",
"com.unity.modules.terrain": "1.0.0",
"com.unity.modules.terrainphysics": "1.0.0",
"com.unity.modules.tilemap": "1.0.0",
"com.unity.modules.ui": "1.0.0",
"com.unity.modules.uielements": "1.0.0",
"com.unity.modules.umbra": "1.0.0",
"com.unity.modules.unityanalytics": "1.0.0",
"com.unity.modules.unitywebrequest": "1.0.0",
"com.unity.modules.unitywebrequestassetbundle": "1.0.0",
"com.unity.modules.unitywebrequestaudio": "1.0.0",
"com.unity.modules.unitywebrequesttexture": "1.0.0",
"com.unity.modules.unitywebrequestwww": "1.0.0",
"com.unity.modules.vehicles": "1.0.0",
"com.unity.modules.video": "1.0.0",
"com.unity.modules.vr": "1.0.0",
"com.unity.modules.wind": "1.0.0",
"com.unity.modules.xr": "1.0.0"
},
"scopedRegistries": [
{
"name": "npmjs",
"url": "https://registry.npmjs.org",
"scopes": [
"com.onesignal"
]
}
]
}

 

I only upgraded to 2021 to be more current and future-proof. I certainly didn't upgrade to use DOTS, or jobs, or AOT burst compiler, or any special feature at all. I upgraded my project from the existing 2020 project, and Unity did it's upgrade thing and I ended up with whatever Unity gave me. I never installed any additional packages, and I don't see any obvious additional packages installed in the package manager.

So... I'm wondering if the native collection memory leak is a new thing, or if it's an old thing that's more verbal in 2021. Because I didn't change anything in the project between upgrading and seeing the messages. I was just trying to figure out how to troubleshoot the memory leak errors based on the errors' own suggestion, which is to enable full stacks. Though it doesn't give any instructions on how to do such a thing. If these memory leak errors are indeed a serious concern, then I would definitely like to get to the bottom of it, and so should Unity. If they're a false flag, then I guess I'll ignore them. I'm ignoring them for now since I can't seem to do anything about them, and they haven't yet created a fatal situation for my app.

 

Well, I tried to install entities in 2021, but it just threw a bunch of errors, so I removed it. I never installed entities in 2020. I also never installed jobs, but I seem to have a menu related to jobs and several warnings & errors related to it. If I can remove it somehow, then I will. However, if I can't remove it then I'll try your menu options above. I'm actually very curious where the memory leaks are originating from anyway.

 

I was able to manually add com.unity.jobs and get the menu item, thank you.

 

Hi,
Using your code above:
Unity.Collections.LowLevel.Unsafe.UnsafeUtility.ForgiveLeaks();
is only in 2022.1 (beta) from what I understand.

https://docs.unity3d.com/kr/2022.1/...wLevel.Unsafe.UnsafeUtility.ForgiveLeaks.html

 

Some suggestions to make this less painful:

1. Have stack tracing options actually in the full stack tracing under build settings (see below)
2. I thought full stack tracing referred to this - apparently not - so make the error message say exactly what the user has to do to enable it.


Hope this helps.

 

Hi.

I dont know how to view the full stack trace. I activated options like Michael_Swan says, and i have a extended log:



But empty with the native collection leak.

I installed the collections package, but i dont find any named like "jobs". The menu jobs dont have any leak option.

Any hint?

 

You have to manually add the com.unity.jobs package in the package manager. Then you will get "Jobs" dropdown menu with "Leak Detection" submenu to turn it on or off or full stack.


And yes, it's very silly that this has to be done. At least there should be a distinction between THESE stack traces and normal stack traces.

 

Thanks Gillissie. Now i can see the leaks problem.

Is was the request to the server in this line:

Code (CSharp):

1. request.uploadHandler = (UploadHandler) new UploadHandlerRaw(bodyRaw);

I implement a dispose to the request when its finish and the leak problem dissapear.

 

Four years ago this was on the todo list. The error is exactly the same today - totally unhelpful. And I tried installing com.unity.entities via package manager (Unity 2021.3.2f1) and it gave loads of errors. Forced Unity to start in safe mode until I removed entities. So I can't get that stack trace turned on.

 

Hey thanks! This helped me solve my problem. Was a UnityWebRequest that I missed a Dispose on.

 

if I try to dispose Native array that is persistent then its a error : NO NO you can not dispose persistent memory etc ...but if i don't i have memory leak .... what is problem in disposing this memory block ?

 

Please post the exact error and example code. You should be able to dispose it, it more sounds like you are trying to dispose the array twice.

 

Error was due the GPUReadBack was holding on to a data after delete on object is called , so i need to make sure that GPU is done whit it so i could call dispose on it .

 

when I want to dispose the byteArray, I get this error message:
ObjectDisposedException: The Unity.Collections.NativeArray`1[System.Byte] has been deallocated, it is not allowed to access it
Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle.CheckWriteAndThrowNoEarlyOut (Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle handle) (at <88d854ea2c91426ebc464f01cd71aa85>:0)
Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle.CheckWriteAndThrow (Unity.Collections.LowLevel.Unsafe.AtomicSafetyHandle handle) (at <88d854ea2c91426ebc464f01cd71aa85>:0)
Unity.Collections.LowLevel.Unsafe.NativeArrayUnsafeUtility.GetUnsafePtr[T] (Unity.Collections.NativeArray`1[T] nativeArray) (at <88d854ea2c91426ebc464f01cd71aa85>:0)
Cwipc.PrerecordedPointCloudReader.GetComputeBuffer (UnityEngine.ComputeBuffer& computeBuffer) (at Library/PackageCache/nl.cwi.dis.cwipc@959f2f9bec/Runtime/Scripts/PrerecordedPointCloudReader.cs:105)
Cwipc.PointCloudRenderer.LateUpdate () (at Library/PackageCache/nl.cwi.dis.cwipc@959f2f9bec/Runtime/Scripts/PointCloudRenderer.cs:150)
But if I don't dispose the byteArray, I got this erroe message:
A Native Collection has not been disposed, resulting in a memory leak. Allocated from:
Unity.Collections.NativeArray`1:.ctor(Int32, Allocator, NativeArrayOptions)
Cwipc.PrerecordedPointCloudReader:GetComputeBuffer(ComputeBuffer&) (at Library\PackageCache\nl.cwi.dis.cwipc@959f2f9bec\Runtime\Scripts\PrerecordedPointCloudReader.cs:100)
Cwipc.PointCloudRenderer:LateUpdate() (at Library\PackageCache\nl.cwi.dis.cwipc@959f2f9bec\Runtime\Scripts\PointCloudRenderer.cs:150)

what should I do with this? This happens when I want to display the point cloud sequences in the cwipc unity package, which is used to playback the point cloud.
Thanks in advance

 

Never post screenshots of code. Use code tags.
The stack trace clearly indicates that you’re getting an exception accessing the data for a disposed collection. The shown code disposes the collection right after it has been created. This would be an error in this code. As it is written currently, it wouldn’t make sense to dispose the allocated buffer anyway, you’re allocating a buffer then throwing it away right after. The logic already disposes the collection that was referenced by byteArray, so the second dispose call seems to serve no purpose and should be removed.

You must always ensure code paths leading to a memory access like GetUnsafePtr have a non-disposed collection when the access occurs.