Addressables Possible Memory Leak Loading Scenes

I'm using addressables to load scenes for our game. In those scenes we have 2D sprite animations. Those sprite animations use sprite atlases to hold the sprites.

When I unload the current scene and move on to the next, sometimes those sprite atlases and animations stick around in memory. I've used the memory profiler and as far as I can tell, the only thing referencing the sprite atlas is the sprites and the only thing referencing the sprites is the animations and the only thing referencing the animation clips are... the animation clips and the sprites. And it's completely random which clips will stick around in memory referencing themselves.


I'm using Resources.UnloadUnusedAssets after loading the new scene. It seems like non-deterministically, the memory isn't being freed.

 

Ah, found it! It's a bug:
https://issuetracker.unity3d.com/is...when-calling-resources-dot-unloadunusedassets

 

Thanks very much for your reply! So this bug is happening in our build. I don't know about the editor, it's too difficult to profile accurately.

I also just noticed that bug is 6+ months old which is very troubling. The way our game is organized, ALL addressables are in one big group. Between levels, we call Resources.UnloadUnusedAssets to get rid of stuff.

I noticed that Unity non-deterministically will leave assets in memory even after that call. Sometimes the call cleans everything up, sometimes it doesn't. And like I said, when I dig in in the memory profiler, I see things referencing themselves at the deepest level. Perhaps it's the same bug? It's actually a huge problem for us because our animations are very big and this bug is causing our game to get killed by the operating system on iPhones.

I'm contemplating breaking up the big default group into a bunch of sub-groups, but that's a tremendous amount of work and I doubt it'll end up being as simple/efficient as the current method. Except the current method doesn't work because of the memory leak.