Question Researching the duplication of colliders

Hi,

For the game I've released one issue is still outstanding, being the bloated subscenes size, about 4x the size of entities' archetype sizes. I suspected colliders to be the issue, and during the Q&A yesterday a Unity representative suggested the same.

So I did a test in a scene of ~30k entities of ~30 prefabs (i.e. I have hundreds and hundreds of identical blocks) and surprisingly it showed me ~4.200 unique BlobAssetReference<Unity.Physics.Collider> instead of expected ~30.

Spoiler: C# code

Code (CSharp):

1.         Dictionary<BlobAssetReference<Unity.Physics.Collider>, int> d = new Dictionary<BlobAssetReference<Unity.Physics.Collider>, int>();
2.        
3.         Entities
4.             .WithEntityQueryOptions(EntityQueryOptions.IncludeDisabled)
5.             .ForEach(
6.             (
7.                 PhysicsCollider pc
8.             )
9.             =>
10.             {
11.                 if (d.ContainsKey(pc.Value))
12.                     d[pc.Value]++;
13.                 else
14.                     d.Add(pc.Value, 1);
15.             }
16.         ).WithoutBurst().Run();
17.  
18.         foreach (var kvp in d)
19.             Debug.LogFormat("{0} : {1}", kvp.Key, kvp.Value);
20.  
21.         Debug.Log(d.Values.Count);

Now, I don't know much about those blobs and how colliders are stored, and maybe all those 4200 are just pointers to the mere 30 unique prefabs and their colliders that I have. Would appreciate any hints to resolve this.

 

Same result, way too many unique values.

No, all scenes are pre-authored and all entities are placed in Editor. I meant that I'm placing usual GameObject prefabs to be converted, so 100% sure there are no unique types, sizes, filters, and material combinations.

Based on the vast majority of pointers having 1-4 references, my guess is that it doesn't recognize similar colliders. Here's a scene view - the selected 8 entities are exactly the same prefabs, but they belong to two different parents, which have their own respective physics bodies and colliders. So despite being unparented, this relationship somehow breaks the recognition of unique colliders? That's my only guess.