How to dispose a Native List ?? [A Native Collection has not been disposed]

Unity Engine
, ,
1

Hello guys,
For the past week I have been working with DOTS. Its amazing I recommend it.
My problem is that I create a new native list at OnEnable inside a blob wrapper. And I need to be persistent through out the game.

    private void OnEnable()
    {
        localLstAttractor = new List<Transform>();
        totalSpawnedBoids = 0;
        entitymanager = World.DefaultGameObjectInjectionWorld.EntityManager;
        currentPosition = this.transform.position;
        ea = entitymanager.CreateArchetype(
            typeof(Translation),
            typeof(Rotation),
            typeof(LocalToWorld),
            typeof(RenderMesh),
            typeof(RenderBounds),
            typeof(Boid_ComponentData)
            );
        debugEntities = new List<Entity>();

        BlobBuilder bb = new BlobBuilder(Unity.Collections.Allocator.Temp);
        boidManagerReference = new BlobAssetReference<BoidManagerBLOB>();
        ref BoidManagerBLOB bmb = ref bb.ConstructRoot<BoidManagerBLOB>();
        BlobBuilderArray<Boid_Manager> blobManagerArray = bb.Allocate(ref bmb.blobManagerArray, 9);
        blobManagerArray[0] = new Boid_Manager
        {
            cohesionBias = cohesionBias,
            separationBias = separationBias,
            alignmentBias = alignmentBias,
            targetBias = targetBias,
            perceptionRadius = perceptionRadius,
            step = step,
            cellSize = cellSize,
            fieldOfView = fieldOfView,
            maxPercived = maxPercived,
            maxObstacleDistance = maxObstacleDistace,
            maxDistanceAttractor = maxDistanceFromAttractor,
            maxDistanceGate = maxDistanceFromGate,
            GatePos = new NativeList<float3>(Allocator.Persistent)
    };
        boidManagerReference = bb.CreateBlobAssetReference<BoidManagerBLOB>(Allocator.Persistent);
        bb.Dispose();
        if (colliderMesh != null)
        {
            col = CreateSphereCollider(colliderMesh);
        }

    }

And in OnDestroy I am disposing the native list and the boidManagerReference

    private void OnDestroy()
    {
        col.Dispose();
        boidManagerReference.Value.blobManagerArray[0].GatePos.Clear();
        boidManagerReference.Value.blobManagerArray[0].GatePos.Dispose();
        boidManagerReference.Dispose();
    }

Even with this things I still get an error from unity saying
A Native Collection has not been disposed, resulting in a memory leak. Allocated from:
Boid_Spawner:OnEnable() (at Assets/Collider Cast/Scripts/Boid_Spawner.cs:82)

And I looked over the activity monitor and I can see that the memory its increasing at each PLAY

Could Anyone explain me a bit what’s happening here ??
As well after I tried it on a different computer. Realised that the fps drops by half if I play multiple times

PS: some parts of the code are from a tutorial on boids and ecs

2

The exact opposite of OnEnable() is technically OnDisable(), not OnDestroy().

Have you tried putting it there instead?

There is no guarantee that OnEnable() and OnDestroy() are called alternatingly.

3

I just tried that and it still give me the same error.

(Just added this to the main post) As well after I tried it on a different computer. Realised that the fps drops by half if I play multiple times

    private void OnDisable()
    {
        col.Dispose();
        boidManagerReference.Value.blobManagerArray[0].GatePos.Clear();
        boidManagerReference.Value.blobManagerArray[0].GatePos.Dispose();
        boidManagerReference.Dispose();
    }
4

First thing to isolate would be your call sequence from the lifecycle of stuff:

Make a tiny script with Start as a coroutine (declare it as such), yield for a second, make the array, yield another second, dispose of it, wait a second and exit.

If that gives an error then either we are misunderstanding how you’re supposed to dispose on these things, or perhaps Unity has a bug. In the latter case you have repro code ready then!