Search Issue Tracker


Fixed in 2022.3.6f1, 2023.1.5f1, 2023.2.0b1, 2023.3.0a1, 7000.0.0a1



Found in






Issue ID




Long Prefab save times when using Unity 2022.2 and higher



Reproduction steps:
1. Open the attached project “PrefabSave”
2. Open the Profiler window (Window > Analysis > Profiler)
3. In the Profiler window select Edit Mode
4. Open the “Asset/Prefabs/Level/Maps/Region_Hills” prefab
5. Disable the Auto Save in the Scene view
5. Select any GameObject in the Scene view and move it to a different position
6. Click on the Save button
7. Wait until Unity Editor finishes saving the prefab
8. Stop the Profiler recording
9. Set the Profiler view to Hierarchy
10. Look for a huge performance spike in the Profiler
11. Navigate to EditorLoop > SceneView.MouseUp > GUIUtility.ProcessEvent() > UIElementsUtility.DoDispatch > OnGUI > EditorOnly [Prefabs.SavePrefab] call

Expected result: EditorOnly [Prefabs.SavePrefab] call takes less than 1400 ms for Self time
Actual results: EditorOnly [Prefabs.SavePrefab] call takes more than 66312.73 ms for Self time

Reproducible with: 2022.2.0a7, 2022.2.13f1, 2023.1.0b10, 2023.2.0a8
Not reproducible with: 2021.3.22f1, 2022.2.0a6
Couldn’t test with: 2020.3.46f1 - A pop up window appears saying “Saving Failed”

Reproducible on: macOS 13.1 (Intel)

Comments (1)

  1. Zachulon

    Apr 07, 2023 05:31

    I am a level designer who works in prefabs and it now takes over 5 minutes every time I save. I try to save often so I don't lose work but with the long wait times I have to think twice. Would love to be able to just quickly save my prefab and keep working. Thank you!

Add comment

Log in to post comment

All about bugs

View bugs we have successfully reproduced, and vote for the bugs you want to see fixed most urgently.