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Not Reproducible



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Issue ID




2018.2 Performance regression in BehaviourManager::Update



We are seeing a 15% performance drop on Windows standalone in some scenarios between 2018.1 and 2018.2.

1. Download attached repro project
2. Run it on Windows Standalone player
3. Compare performance on 2018.1.0f1 and 2018.2.0b1.

2018.2.0b1 renders 25898 frames in 60 seconds. 2018.1 renders the same amount of frames in 51.788 seconds, which is whole 8.212 seconds (15.8%) faster. Out of that slowdown, BehaviourManager::Update contributes a significant amount of time:

2018.1.0f1: 5563 ms
2018.2.0b1: 8017 ms
Delta: 2454 ms

Note, these measurements were taken after profiling the parent case, and split the bug in several smaller bugs because scripting is not the only area that got slower. The absolute timings will be different depending on the machine, but the performance decrease in percentage should be similar.

Comments (8)

  1. shubhamswaraj2021

    Aug 18, 2020 09:44

    good one <a href="">lyricsauto</a>

  2. WilliamRiley

    Feb 12, 2020 05:36

    Very informative content on performance regression in behaviour manager. It’s so interesting and I’ll enjoyed to read it. Thanks for sharing with us. Emily,

  3. omar8star

    Jun 20, 2019 14:07

    as the frame rate drop from 2018.1 to 2018.2 is pretty significant and has undone a lot of my work to get a stable 60FPS - now sitting at more like 50FPS.

  4. Alvarezmd90

    Oct 23, 2018 14:54

    It has a ridiculously bad performance. I don't know what happened but my GTX 1080 TI MSI Founders Edition struggles to get above 500fps in a scene that is pretty low poly. It is basically the scene from F.E.A.R. , a game released back in 2005. I separated every room into parts and still, unacceptable speed for my beast of a pc.

  5. lukaszunity

    Sep 06, 2018 06:56

    We are unable to reproduce a regression in performance in BehaviourManager::Update in 2018.2.

    If you are experiencing a regression in performance for your project when upgrading to new Unity version, please submit a separate bug so we can verify and investigate it.

  6. TigerFudo

    Jul 15, 2018 03:02

    Same issue for me.

  7. mgeorgedeveloper

    Jul 06, 2018 19:16

    Please note that Unity team has CONFIRMED it is reproducible:

    "Unity Technologies was able to reproduce the regression, which can be found in the public issue tracker now:

    Good job and thank you, QA!"

    Here's the thread:

  8. mgeorgedeveloper

    Jul 06, 2018 19:13

    This is definitely reproducible - in our own project, I saw an immediate drop in frame rate matching above description. I was glad to see this is in the list of known issues to be addressed. I hope this will be fixed somehow, as the frame rate drop from 2018.1 to 2018.2 is pretty significant and has undone a lot of my work to get a stable 60FPS - now sitting at more like 50FPS.

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