[Jobs][Lags] JobTempAlloc has allocations that are more than 4 frames old

I'm glad the 4 frames limit on jobs is being removed, it's something that severely limits the use cases of jobs where they would otherwise be ideal. It also ties your code to the framerate, causing all sorts of "different hardware" problems. Say your job takes 30ms to finish; no bug at 60FPS, hard to track bug at 144FPS.

 

After some research I found another case when this problem occurs. In our case while using WebGL and the Particle System..... kind of like @castor76 problem but slightly different.

I'm using Unity 2018.3.0f2

Here are some details of the bug-report

EDIT: It's even simpler. Just publish an empty scene with fresh out-of-the-box particle system and (de)activate the Trail-Module. If active it will trigger the error.

 

I'm having this issue and between the hundreds of "JobTempAlloc has allocations that are more than 4 frames old.."
it says "To Debug, enable the define: TLA_DEBUG_STACK_LEAK in ThreadsafeLinearAllocator.cpp. This will output the callstacks of the leaked allocations"

Anyone figure out how to do this? I cant seem to.
Here are some of those crash reports:

one dude: https://pastebin.com/CcjPkuHj
other dude: https://pastebin.com/Ce0TL821
another dude: https://pastebin.com/CiNyXn04

 

The bug was reported under case number 1114502
https://fogbugz.unity3d.com/default.asp?1114502_j9b584o63nk4fib2

 

Not fixed in 2018.3.1f1

Build Target: WebGL
Empty Scene -> New Particle System -> Active trails will trigger the error in build

 

That is some sad news - was happy to see a new build today but looking at the release notes I was kinda let down

 

Has this been fixed? I have the problem now in 2018.3 where its saying this in the browser:

Internal: JobTempAlloc has allocations that are more than 4 frames old - this is not allowed and likely a leak


Then gives memory warnings

UnityLoader.js:4 GC Warning: Repeated allocation of very large block (appr. size 7192576):
printErr @ UnityLoader.js:4
UnityLoader.js:4 May lead to memory leak and poor performance
printErr @ UnityLoader.js:4
UnityLoader.js:4 GC Warning: Repeated allocation of very large block (appr. size 3596288):
printErr @ UnityLoader.js:4
UnityLoader.js:4 May lead to memory leak and poor performance


Then crashes because of out of memory

 

Same here. 2018.3.0f2 WebGL build spams the console with this error. Going back to 2018.2 makes it go away.

 

Any estimate on when the 4 frame limit will be completed? Also would it be bad if i had jobs runnning for up to 15 seconds?

 

Well thats odd....
As you can see here: https://fogbugz.unity3d.com/default.asp?1114502_j9b584o63nk4fib2 the case was closed but the problem still exists in the current version 2018.3.3f1.

@Unity @Marco-Trivellato is there anything we can expect regarding this bug?

 

Hey everyone: Version 2018.3.4 fixed the problem! *yaay* ​

 

...it did? I am on 2018.3.4 and I'm here because I'm getting spammed by the warning right now.

 

@Joachim_Ante

Well, your own patchnotes say that you did



And I tested it: New scene -> add particle system -> activate trails -> build as WebGL -> no problem

Maybe we are talking about two different problems?

 

Getting the same error all the time in 2018.3.5 when using a particle system.

 

Ah, I see! Thank you for clarifying that.
In my case the bug was indeed only about the particle system, I did not recognized any other problems regarding the job system. Sorry for mixing things up.

 

Hello,

This is still happening to me as well on Unity 2018.2.14f1. Any fixes for this, I don't believe I am using any job system.

Thanks!

 

Hello
I get this problem with 2018.3.6f1, only when i enable "deep profile" in the profiler.
I get even more message /details with 2019.1.0b4 and 2019.2.0a6.

That happens randomly depending on the state of the project (sometimes disappears, sometimes come back), and greatly disturbs the profiler (FPS greatly reduced).

I am not using jobsystem (but i tried it briefly and cancelled).

 

I am having the same problem, even with no self-made code. Help?

 

Any chance of adding this fix to your only LTS release so far (2017.4)? Getting this bug when importing assets from the store.

 

So in general...
Example with documentation like a+b is..... no comment.
Question then is: how to use jobs in real scenarios?
We can't use references, we can't use static data (sic!)

so let's imagine real world scenario - pathfinding being calculated on separate thread.

we have a List<Tile> MapTiles - keeping information albout all tiles on the map
now how to use job system to calculate pathinding and get the result
(result should be Tile[] or int[] (tiles have own ID) or List<Tile>)

we can't pass our MapTiles to the job, we can't refer to it, we can't make MapTIles static to be accessible from the job...

So... for what purposes is this job system for?

BTW - 2019.1.0f2 - problem still exists

 

I've been seeing this warning a lot in clean projects lately.

Mainly when switching scenes.

Using 2019.1

 

As JIMBOB pointed out, I get this using Async Navmesh generation, which was written by Unity if I'm not mistaken. There's even an issue open about it:
https://github.com/Unity-Technologies/NavMeshComponents/issues/122
Upgrading to 2019.1 is not an easily chosen path, now or ever.

 

I'm getting the same problem randomly it seems.

It goes away for roughly 20 min or so whenever I restart my editor but then comes back. I made no changes to any code between restart and warning appearing. I've also started and stopped my code (still unchanged) multiple times without the warning showing up. Very strange.

 

I think I have managed to find the cause for this and it seems like it is a Unity bug.

Background: I have an IJobParallelFor set up that is scheduled in one FixedUpdate() and finished in the next FixedUpdate(). The same frame it is finished it gets re-scheduled again and so the cycle continues. This job calculates some physics forces so this is needed. If I limit the framerate through V-Sync this message disappears which leads me to believe that there is some code checking if the job has been finished inside 4 Update() calls, not taking into account if the job was scheduled inside FixedUpdate() since only one FixedUpdate() passes between scheduling and finishing. It also means that the error is entirely framerate dependent.
In the official Unity documentation it says that finishing the job just after it was scheduled is a bad design, and yet if we want to use job system with physics that would mean either finishing jobs inside Update() instead of FixedUpdate() which is not always practical. So please investigate this.

 

This bug still appears on 2019.1.1f1, specifically with LocalNavMeshBuilder using AsyncOperation.
When restarting unity and not running AsyncOperation from NavMeshBuilder.UpdateNavMeshDataAsync(), the leak is not there, everything is fine.

It seems async does not stop, keeps running even after exiting play mode, it will eventually freeze editor for me

 

I have managed to get rid of the error by getting rid of the struct I was allocating inside the job. Still - it is still a bit weird that we can not use structs if we want to run jobs in FixedUpdate().

 

I am getting the same thing on 2019.1.6

If I create and dispose the NativeArray on the same frame, I do NOT get this warning message. However, if I were to create, for example, in OnEnable() and dispose in OnDisable() I get this message. Does the create/dispose has to be done in the same frame?

What am I doing wrong here?

Here's the code:
This gives me the message in question (4 frames old...)

Code (CSharp):

1. using Unity.Collections;
2. using Unity.Jobs;
3. using Unity.Mathematics;
4. using UnityEngine;
5. using UnityEngine.Jobs;
6. using Unity.Burst;
7. public class TestJob : MonoBehaviour
8. {
9.     public float3 velocity;
10.     public float3[] velocities;
11.     public float3[] positions;
12.     public Transform testPrefab;
13.     public Transform[] transforms;
14.     public int count = 1000;
15.     public bool update;
16.     public bool useJobs;
17.  
18.     public SimpleMoveJob simpleMoveJob = new SimpleMoveJob();
19.  
20.     private void Awake()
21.     {
22.         Unity.Mathematics.Random random = new Unity.Mathematics.Random(1);
23.         velocities = new float3[count];
24.         positions = new float3[count];
25.  
26.         transforms = new Transform[count];
27.         for (int i = 0; i < count; i++)
28.         {
29.             transforms[i] = Instantiate<Transform>(testPrefab);
30.             float3 bulletPos = transform.position;
31.             bulletPos += random.NextFloat3(10, 60f);
32.             transforms[i].position = bulletPos;
33.             velocities[i] = velocity;
34.             positions[i] = transforms[i].position;
35.         }
36.  
37.    
38.     }
39.  
40.     private void OnEnable()
41.     {
42.         simpleMoveJob.posX = new NativeArray<float>(count, Allocator.TempJob);
43.         simpleMoveJob.posY = new NativeArray<float>(count, Allocator.TempJob);
44.         simpleMoveJob.posZ = new NativeArray<float>(count, Allocator.TempJob);
45.  
46.         simpleMoveJob.vX = new NativeArray<float>(count, Allocator.TempJob);
47.         simpleMoveJob.vY = new NativeArray<float>(count, Allocator.TempJob);
48.         simpleMoveJob.vZ = new NativeArray<float>(count, Allocator.TempJob);
49.     }
50.  
51.     private void OnDisable()
52.     {
53.         simpleMoveJob.posX.Dispose();
54.         simpleMoveJob.posY.Dispose();
55.         simpleMoveJob.posZ.Dispose();
56.  
57.         simpleMoveJob.vX.Dispose();
58.         simpleMoveJob.vY.Dispose();
59.         simpleMoveJob.vZ.Dispose();
60.     }
61.  
62.     private void Update()
63.     {
64.         if (update)
65.         {
66.             if (!useJobs)
67.             {
68.                 float deltaTime = Time.deltaTime;
69.  
70.                 for (int i = 0; i < count; i++)
71.                 {
72.                     positions[i] += velocities[i] * deltaTime;
73.                     transforms[i].position = positions[i];
74.                 }
75.             }
76.             else
77.             {
78.  
79.                 for (int i = 0; i < count; i++)
80.                 {
81.                     simpleMoveJob.posX[i] = positions[i].x;
82.                     simpleMoveJob.posY[i] = positions[i].y;
83.                     simpleMoveJob.posZ[i] = positions[i].z;
84.  
85.                     simpleMoveJob.vX[i] = velocities[i].x;
86.                     simpleMoveJob.vY[i] = velocities[i].y;
87.                     simpleMoveJob.vZ[i] = velocities[i].z;
88.                 }
89.  
90.                 simpleMoveJob.deltaTime = Time.deltaTime;
91.  
92.                 JobHandle simpleMoveJobHandle = simpleMoveJob.Schedule(count, 1000);
93.                 simpleMoveJobHandle.Complete();
94.  
95.                 for (int i = 0; i < count; i++)
96.                 {
97.                     positions[i].x = simpleMoveJob.posX[i];
98.                     positions[i].y = simpleMoveJob.posY[i];
99.                     positions[i].z = simpleMoveJob.posZ[i];
100.  
101.                     transforms[i].position = positions[i];
102.                 }
103.             }
104.         }
105.     }
106. }
107.  
108. [BurstCompile]
109. public struct SimpleMoveJob : IJobParallelFor
110. {
111.     public NativeArray<float> posX, posY, posZ;
112.  
113.     [ReadOnly]
114.     public NativeArray<float>vX, vY, vZ;
115.     [ReadOnly]
116.     public float deltaTime;
117.  
118.     public void Execute(int i)
119.     {
120.         posX[i] += vX[i] * deltaTime;
121.         posY[i] += vY[i] * deltaTime;
122.         posZ[i] += vZ[i] * deltaTime;
123.     }
124. }

This one runs with no warnings:

Code (CSharp):

1. using Unity.Collections;
2. using Unity.Jobs;
3. using Unity.Mathematics;
4. using UnityEngine;
5. using UnityEngine.Jobs;
6. using Unity.Burst;
7. public class TestJob : MonoBehaviour
8. {
9.     public float3 velocity;
10.     public float3[] velocities;
11.     public float3[] positions;
12.     public Transform testPrefab;
13.     public Transform[] transforms;
14.     public int count = 1000;
15.     public bool update;
16.     public bool useJobs;
17.  
18.     public SimpleMoveJob simpleMoveJob = new SimpleMoveJob();
19.  
20.     private void Awake()
21.     {
22.         Unity.Mathematics.Random random = new Unity.Mathematics.Random(1);
23.         velocities = new float3[count];
24.         positions = new float3[count];
25.  
26.         transforms = new Transform[count];
27.         for (int i = 0; i < count; i++)
28.         {
29.             transforms[i] = Instantiate<Transform>(testPrefab);
30.             float3 bulletPos = transform.position;
31.             bulletPos += random.NextFloat3(10, 60f);
32.             transforms[i].position = bulletPos;
33.             velocities[i] = velocity;
34.             positions[i] = transforms[i].position;
35.         }
36.  
37.    
38.     }
39.  
40.  
41.     private void Update()
42.     {
43.         if (update)
44.         {
45.             if (!useJobs)
46.             {
47.                 float deltaTime = Time.deltaTime;
48.  
49.                 for (int i = 0; i < count; i++)
50.                 {
51.                     positions[i] += velocities[i] * deltaTime;
52.                     transforms[i].position = positions[i];
53.                 }
54.             }
55.             else
56.             {
57.  
58.                 simpleMoveJob.posX = new NativeArray<float>(count, Allocator.TempJob);
59.                 simpleMoveJob.posY = new NativeArray<float>(count, Allocator.TempJob);
60.                 simpleMoveJob.posZ = new NativeArray<float>(count, Allocator.TempJob);
61.  
62.                 simpleMoveJob.vX = new NativeArray<float>(count, Allocator.TempJob);
63.                 simpleMoveJob.vY = new NativeArray<float>(count, Allocator.TempJob);
64.                 simpleMoveJob.vZ = new NativeArray<float>(count, Allocator.TempJob);
65.  
66.                 for (int i = 0; i < count; i++)
67.                 {
68.                     simpleMoveJob.posX[i] = positions[i].x;
69.                     simpleMoveJob.posY[i] = positions[i].y;
70.                     simpleMoveJob.posZ[i] = positions[i].z;
71.  
72.                     simpleMoveJob.vX[i] = velocities[i].x;
73.                     simpleMoveJob.vY[i] = velocities[i].y;
74.                     simpleMoveJob.vZ[i] = velocities[i].z;
75.                 }
76.  
77.                 simpleMoveJob.deltaTime = Time.deltaTime;
78.  
79.                 JobHandle simpleMoveJobHandle = simpleMoveJob.Schedule(count, 1000);
80.                 simpleMoveJobHandle.Complete();
81.  
82.                 for (int i = 0; i < count; i++)
83.                 {
84.                     positions[i].x = simpleMoveJob.posX[i];
85.                     positions[i].y = simpleMoveJob.posY[i];
86.                     positions[i].z = simpleMoveJob.posZ[i];
87.  
88.                     transforms[i].position = positions[i];
89.                 }
90.  
91.                 simpleMoveJob.posX.Dispose();
92.                 simpleMoveJob.posY.Dispose();
93.                 simpleMoveJob.posZ.Dispose();
94.  
95.                 simpleMoveJob.vX.Dispose();
96.                 simpleMoveJob.vY.Dispose();
97.                 simpleMoveJob.vZ.Dispose();
98.             }
99.         }
100.     }
101. }
102.  
103. [BurstCompile]
104. public struct SimpleMoveJob : IJobParallelFor
105. {
106.     public NativeArray<float> posX, posY, posZ;
107.  
108.     [ReadOnly]
109.     public NativeArray<float>vX, vY, vZ;
110.     [ReadOnly]
111.     public float deltaTime;
112.  
113.     public void Execute(int i)
114.     {
115.         posX[i] += vX[i] * deltaTime;
116.         posY[i] += vY[i] * deltaTime;
117.         posZ[i] += vZ[i] * deltaTime;
118.     }
119. }

 

Never mind, I think I figured it out.

If I set these as Allocator.Persistent no warnings.

Code (CSharp):

1.     private void OnEnable()
2.     {
3.         posX = new NativeArray<float>(count, Allocator.Persistent);
4.         posY = new NativeArray<float>(count, Allocator.Persistent);
5.         posZ = new NativeArray<float>(count, Allocator.Persistent);
6.  
7.         vX = new NativeArray<float>(count, Allocator.Persistent);
8.         vY = new NativeArray<float>(count, Allocator.Persistent);
9.         vZ = new NativeArray<float>(count, Allocator.Persistent);
10.     }

Can someone please explain the difference between Allocator.Temp and Allocator.TempJob? How should the life cycle of each be? are they both intended to work during one frame?

https://docs.unity3d.com/ScriptReference/Unity.Collections.Allocator.html
Doc. doesn't really explain much.

 

Temp is for new containers allocated inside job

 

I am getting this error on 2019.2.0b3 and 2019.3.0a5, using Native Arrays and Native Hash Maps.

 

I am on Unity 2019.1.5f1 and am suddenly getting this error now. It was fine a few days ago, but now all of a sudden it starts every time I click play. I cannot find the source of the issue as it was as stated fine a few days ago, and I am currently not using ECS or Jobs in my project, except for in the ECS and Jobs example files from the GitHubs.

Is there some sort of update feature I am unaware of for this?

 

Not sure if this is related but, I believe some of the dependencies (forget exactly which) were updated. Might want to check the package manager. I'd back things up though since these updates may create other errors etc..

 

I am having the same issue without any kind of Job System usage.


I have this error when I run the project within the iOS device, within Unity editor, I am not getting any kind of error messages.
Unity Version 2018.4.2

 

I have the same issue in Unity 2019.1.8f1

bug report id: 1170392

 

I've been getting this forever. It is definitely an internal Unity problem and I am surprised it has been around as a bug for so long. At least back to 2017 Unity from my research.

 

This error message just started spamming my console on 2019.1.10f1 with no apparent changes on my end to cause them.

I'm not using the job system, I haven't made any changes that would cause this. It wasn't happening yesterday and I checked out yesterday's commits... still happening.

 

When did you install 2019.1.10??

 

According to the git commit log... July 18th.

 

Yeah, I've been getting this error forever. Only happens when I hit play, never before I start up the scene. I have VR installed. I am not sure what else it could be.

 

Sent a +1 bug report regarding this one. Got these constantly spamming into console.

It wasn't that bad on 2019.1 / 2019.2, but on 2019.3 it completely destroyed my FPS (in editor).

(Case 1173391) <- Always occurs for me

For some reason I think it might be related to the hybrid render package / moving camera.

 

It's no longer happening today, literally one day later. I can't think of anything I did to fix it either.

 

@xVergilx I am running the hybrid render package and that could be the reason. I find as the day goes on I get more and more of the errors.

 

I have to ask goose, what version of Unity are you using and what platforms are you targeting?

I feel like you're not getting much of a response because as far as I'm aware most if not all internal causes of this have been fixed in various 19.x builds. I have not seen this issue appear in months outside of screwing up something myself.

Are you sure it's not your code causing the issue?

The annoying thing is if you screw up something then the warning will stay until you restart Unity.

(I did recently have this popup in an Android build but it was simply a bad link.xml that I had forgot to update. And I can easily create the warnings due to exceptions or not properly returning job handles but the warning is working as intended for this.)

 

The problem is that you can't tell 100%. Those warnings are really poorly written.
It doesn't help that they continue to spam constantly when you don't know what causing them, or how to fix it.

I've had similar messages popup even in a project that didn't have a Jobs packages installed. The issue was that I've installed newer drivers, and didn't reboot the pc. Unity simply couldn't handle driver reload correctly (even after restart).

Things like this is impossible to track down with these messages.
UT has to do something about them, not just plain tell "Okay you can't do anything, spam the S*** out of our bug tracker, we'll figure 1 eternity later what's going on".

 

@tertle I am using Unity 2019.1.8, targeting VR and windows. Gonna update to 2019 now. The errors that throw when I haven't deallocated a job in time are different. They have a different format and don't tell you to turn on a weird stack trace. These are ones that are internal to the Unity Engine. It is pretty clear from @DanielSuperKing 's report that it happens somewhere deep inside Unity's stuff since it came out of nowhere and then went away. "TLA_DEBUG_STACK_LEAK in ThreadsafeLinearAllocator.cpp" is something to do with a c++ file I think.

I'll see if 2019.2 fixes it, but there are enough people continuing to report this problem that I don't think it is from my code. Plus I am about 95% sure I've deallocated every job either in the same frame or in the next frame in my code. Of course I could be wrong, but I am pretty sure if I don't deallocate a job it gives me a proper stack trace with the disposal sentinel.