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transform syncing behavior in light of job system

Discussion in 'Data Oriented Technology Stack' started by snacktime, Jan 11, 2018.

  1. snacktime

    snacktime

    Joined:
    Apr 15, 2013
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    2,370
    So in 2017 I hit a case where transform syncing would abruptly skyrocket at a certain threshold. I filed a bug report for it 985751.

    But in 2018 while the behaviour is still there, it takes a good number more rigidbodies to trigger. On my system I hit it at right around 5000.

    So I'm curious if this is just the new norm when not using the job system. Which I could kind of see making sense in a way.

    Also I seem to remember a post about this somewhere, but can someone confirm that when updating rigidbodies via the job system we should have auto sync transforms off?
     
  2. yant

    yant

    Unity Technologies

    Joined:
    Jul 24, 2013
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    290
    Hi,

    While the bug you mentioned is being processed by the QAs, I can confirm that using any job-based approaches has a requirement of having to disable the automatic transform sync with physics. This is because one can't run multiple sync's in parallel and you pretty much never know for sure when a sync might be triggered in the automatic mode.

    Actually, we were considering to make it so that starting from some Unity version all the new projects would have automatic sync off by default. I believe we're going to do that as more and more groups of devs have to disable the automatic sync anyways.

    Hope that helps.

    Anthony
    R&D Physics
     
  3. GameDevCouple_I

    GameDevCouple_I

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    Good idea, I think any serious dev who understands this issue will ask for it to be OFF by default, I for one would much prefer if we controlled this ourselves!
     
  4. Peter77

    Peter77

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  5. GameDevCouple_I

    GameDevCouple_I

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