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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




Increased Script Assembly reload time



Reproduction steps:
1. Open the attached case_1317926-assembly-reload-slow - project
2. Open Scripts/AnimalMovement script and uncomment line 32
3. Save changes
4. Switch back to Unity
5. Repeat the operation 10 times (to get average numbers)
6. Open the Editor.log
7. Observe
- ImportAndPostprocessOutOfDateAsset timing
- Finished script compilation in timing

Baseline version is 2020.1.17f1
Regression confirmed in 2020.2.7f1

Reproducible with: 2020.2.0a1, 2020.2.7f1, 2020.3.1f1, 2021.1.0f1, 2021.2.0a10
Not reproducible with: 2018.4.33f1, 2019.4.22f1, 2020.1

  1. Resolution Note (2021.2.X):

    Our teams are actively working at resolving this issue, but because this issue is requiring more work than a single bug fix, we are closing this issue and we will give further updates on this forum thread

    Thank you for your feedback, patience and understanding.

Comments (8)

  1. jamesalbrecht

    Nov 06, 2023 07:47

    Read more

  2. brucewill

    Aug 29, 2023 09:46

    Teeth whitening pens are a convenient and affordable way to whiten your teeth at home. They are small, portable devices that contain a whitening agent or gel which is applied directly to the teeth.

  3. organicdegree

    Apr 26, 2023 02:50

    I recreated this project from my main project just to get this time down, and with BOTH compiling and reloading script assemblies it was at 100 seconds in the large project. The large project was big, at 150GB, and had many different code assets. So ok.

  4. bmod

    Mar 19, 2023 00:08

    Absolute garbage, iteration time is the ONLY reason to use an editor like Unity. It used to be fast, now it's unusable.

    Not is it only unresolved, it's getting worse with every major version as well.

    Goodbye Unity, hello Unreal.

  5. JezMK

    Oct 26, 2021 02:35

    This issue was referenced in the past 5 LTS releases for 2020.3.x, other than the last one, as a "known issue". In the latest release, 2020.3.21f1, there's no mention of it.
    Is it fixed, or just missing from the known issues list?

  6. stonstad

    Aug 25, 2021 14:32

    Is there an update for this issue?

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