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[GPU PLM]Fallback from CPU Lightmapper in CL_MEM_OBJECT_ALLOCATION_FAILURE when baking ArchVizPRO when view prioritization is on

Global Illumination


For reproducing this bug you'll need to download the ArchVizPRO Interior Vol. 6 package from here:

Steps to repro:
1. Open downloaded project and 'AVP6_Desktop' scene;
2. Open Player Settings window (Edit>Settings>Player);
3. Set Color Space to Linear;
4. Open Lighting window (Window>Rendering>Lighting Settings);
5. In the Lightmapper field of the Lighting window select Progressive GPU (Preview);
6. In the Lighting window click 'Generate Lighting' button;
7. Wait until the lighting is baked.

Expected result:
The lighting is baked successfully on GPU Lightmapper.

Actual result:
The lightmapping backend falls back to CPU LM with the following message:
(Filename: C:\buildslave\unity\build\Editor/Src/GI/Progressive/OpenCL/OpenCLCheck.cpp Line: 122)

OpenCL Error. Falling back to CPU lightmapper. Error callback from context: CL_MEM_OBJECT_ALLOCATION_FAILURE

(Filename: C:\buildslave\unity\build\Editor/Src/GI/Progressive/OpenCL/OpenCLCheck.cpp Line: 122)

See attached screenshot for Editor console and GPU load in Windows Task Manager.

- Reproducible in 2019.2.0a1, 2019.1.0a2, 2018.3.0b3;
- Reproducible on Windows 10 with GeForce 1070GTX having 8GB of VRAM;
- Editor has crashed once when baking this project with view prioritization enabled. See the Editor log in the comments. This, however, happened only once and doesn't happen after rebaking.
- Reproducible with Lightmap resolution 4096 and 1024;
- Reproducible with and without view prioritization enabled.

  1. Response avatar

    Resolution Note:

    The memory usage in GPU Lightmapper is being addressed in Unity 2020.1 and 2020.2. The memory optimizations are unfortunately too complicated to backport to 2019.3. We are sorry for the inconvenience. The 2020.1 alpha already has a greatly reduce memory footprint.

Comments (8)

  1. F7083405d14f1a056d5665f0b08424c6?d=mm


    Apr 30, 2020 21:18

    Same in my project on GTX 960 2GB
    Unity 2019.3.10f1

  2. 00fea7dd4d021888cebf94eaa80dede7?d=mm


    Dec 12, 2019 16:31

    So this particular bug has been around for over a year and still hasn't been fixed. It has cost me and my client a lot of trouble/time.

  3. 3b6a4ff1d452c2767ff2250f7a432052?d=mm


    Sep 26, 2019 16:49

    I'd like to add that:
    - This issue happen to my project without ArchvizPro with any Unity above 2019.1.14f1 - works fine before up to (including) this version
    - In any version above 2019.1.14f1, disabling light probes makes this issue disappear and allows to bake

    It's currently blocking us from upgrading above 2019.1.14f1 - closely monitoring this bug :)

    Thanks in advance for you work!

  4. 82ee57b25de1f5316e989181e3ea3aa7?d=mm


    Jun 24, 2019 11:51

    Same problem on GTX 1070 using Unity 2019.1.7f1

  5. 3b6a4ff1d452c2767ff2250f7a432052?d=mm


    Jun 14, 2019 14:37

    Same with RTX 2080

  6. Dd1f2b1aa273769e2ecbde03f880bb82?d=mm


    Jan 22, 2019 20:19

    same on gtx 1070 ti

    unity 2018.3.2f1

  7. D427d155a127d8152b6d91981b8b9376?d=mm


    Dec 17, 2018 13:44

    same with nvidia 980ti with drivers updated to latest .

  8. C2408d7ebebda24e3e87c7ba22645dde?d=mm


    Dec 11, 2018 15:32

    same on gtx 970
    unity v 2018.3.0f1

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