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Postponed means that the issue was either a feature request or something that requires major refactoring on our side. Since that makes the issue not actionable in the close future we choose to close it as Postponed and add it on our internal roadmaps and technical debt pages instead.




Found in











Issue ID




LightingData.asset being too big causes Scene corruption and Size overflow in allocator error

Progressive Lightmapper


Steps to reproduce:
1. Open user-submitted project
2. Open Scene Scenes/xx
3. Wait for Unity to exit with the following error:

Size overflow in allocator error
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

Reproduced with: 2017.1.1f1, 2017.4.8f1, 2018.2.3f1, 2018.3.0a8, 2020.1.0a23.2984, 2021.2.0a17

  1. Resolution Note (2021.2.X):

    The file serialization system needs 64bits support, until that happens, please split the scene into smaller chunks to avoid exceeding the maximum 2GB size.

Comments (6)

  1. LtKelleyUSMC

    Oct 15, 2021 18:16

    Same here. Using 2020.2.7f1. Have 2 scenes. 1: Loading scene to connect to Photon, and Game Scene where all game play takes place, which is a rather large scene, and I noticed, when trying to Generate Lighting, it just seems to go on forever, but did see a size of 2GB, so I switched over to Auto, and reduced the resolution from 1024, to 256, and apparently, this is still to large, SO, am having to delete my TEMP and LIBRARY folders (3,452,886 items and 3.96Gb of data), and will see if I can load my project after that. Perhaps need to limit the size of my Game Scene, and break it up into different scenes.

  2. kiloWhat

    Nov 19, 2020 14:09

    Same. Using 2019.4.3f1.
    It bakes a 2.1GB file out in any resolution. That 0.1GB is really driving me nuts.

  3. mmena

    Sep 04, 2020 10:19

    Same thing here, 2.4gb and unity project/scene won't open

  4. unityinhance

    Aug 22, 2019 16:54

    Anything over 2gb causes this issue. Can not assign lighting data to scene.

  5. GordGames

    Jan 15, 2019 00:54

    Me too... did a big light bake in 2018.2.20f1, it made a 3.1gb lightingdata.asset and now it won't load Unity.

  6. GordGames

    Jan 15, 2019 00:52

    Me too... did a big light bake in 2018.2.20f1, it made a 3.1gb lightingdata.asset and now it won't load Unity.

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