Unloading active scene async causes huge enlighten lag spike

Unity Engine
, , , ,
1

image
image1095×314 18.6 KB

As you can see here, unloading this scene causes a ridiculously long freeze in my game. A couple things to note:

  • This only happens when I bake any scene’s lighting with realtime GI enabled
  • This happens to all scenes baked with realtime GI enabled, some lag longer than others
  • I am unloading using Addressables.UnloadSceneAsync
2

Hmm. The call tree doesn’t give away much information. Part of the native portion is probably cut off.

A few questions:

  • How big are the scenes you are playing around with?
  • If you make a tiny scene with realtime GI enabled (just a few cubes or something), do you still get a big spike?
  • What kind of machine are you testing on?

For spikes this long you should file a bug report if this is blocking you. It’s difficult to give better advice without access to the project.

If you want to try troubleshooting further yourself, you can often use a native profiler like Very Sleepy to get a better view of what is going on.

3

The scenes aren’t that big. They’re a decently small arena that runs on mobile and PC at 60 FPS constant just fine, the only issue is the unloading. When I make a tiny scene, there is no spike. I’m gonna try debugging by slowly adding in geometry from the original scene, and rebaking as I go. I probably will file a bug report if I don’t get good results from that debugging.

Here’s a picture of it for reference

image
image1110×730 79.2 KB

4

I’ve filed a bug report with all the necessary information and the files for my scene isolated in a test project to make it easily reproducible. IN-85410

1 Like
5
1 Like
6

IMG_3507
IMG_35071095×436 43 KB

We encountered the same issue and were unable to resolve it.
We found on a forum that this issue was already discovered on November 10, 2023, and again on September 25, 2024, but it still hasn’t been fixed to this day.
This issue has now forced us to delay the game’s release.

7

In addition, we have also discovered a new problem. Real-Time GI Bake does not support Terrain Hole. The baked light does not pass through the hole, causing the hole to be completely black.