596
votes
Started

Multi core / multi thread physics

Physics

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Virtually every recently manufactured computer has at least 2 cores, yet Unity only uses one of them. Even relatively simple physics simulations (such as a small interactive cloth or a rope made of colliders and joints) can easily max out that single core on even the fastest computers. It's time for Unity to be updated to support current technology. See this thread for more info:
http://forum.unity3d.com/threads/71357-Multi-core-physics

Response-avatar

jonas echterhoff

May 15, 2014

Physx 3.3 will have this, and is planned for Unity 5.0.

Comments (22)

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ITCL_RV
Mar 24, 2014 15:02

This will be included in Unity 5. Great.
http://forum.unity3d.com/threads/234931-Unity-5-is-coming-and-more!/page13?p=1560424&viewfull=1#post1560424

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RElam
Apr 11, 2013 05:56

@JasonB
You're the first developer I've ever heard that thinks GPU physics should happen before multi-threaded physics, and I definitely agree with the majority. GPU physics has limited usefulness on limited platforms, only good reason to support GPU physics over this is if you work for NVidia :).

@DanielSig
Perhaps we're thinking of different things, but general API thread safety would be a far more daunting task than this, and generally physics is run in fixed steps and thus is more damaging to user experience when it becomes a bottleneck than most other things (since it's difficult to scale in most cases). In the bang for the buck category, I'd say this ranks significantly higher than a generally thread safe API.

Keep in mind, depending on implementation, this could turn physics from a constantly blocking operation to an effectively free one on remotely modern hardware, with no extra requirements placed on users. That's pretty attractive, IMO.

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Causeless
Mar 31, 2013 22:35

100% yes.

0762380d366fe67ba8560198f4f10eab?d=mm
ITCL_RV
Jan 23, 2013 12:24

We also need it.
It would be a fantastic performance improvement for Unity

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TechKid64Bit
Feb 15, 2012 12:10

I agree, unity is definetly lacking functionality and features, with the addition of this we can push ot games to the limit! without worrying about stability issues etc.

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oulehui
Jan 07, 2012 04:00

I need multi thread physics~!!!

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Wolfos
Nov 10, 2011 09:31

I want my computer to be maxed out while baking lightmaps! Now I can play Minecraft in the background, on a Core 2 Duo laptop!

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DanielSig
Oct 31, 2011 15:26

They should start out by at least making things thread safe... THEN make the physics multi threaded

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web76
Sep 08, 2011 07:25

It is very limitating at the moment, if not Gpu accel, it should at least be multithread.

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JasonB
Aug 29, 2011 16:49

I think people who voted this up would be interested in my suggestion called "GPU PhysX". The biggest problem with Unity's PhysX implementation isn't that it's not multi-threaded, but that it doesn't use our Nvidia GPUs, which was supposed to be the biggest draw of PhysX to begin with! I do agree that multi-threaded physics should also be a priority, but I would love to see GPU PhysX enabled first, because it would be so simple (relatively) to do, especially seeing how this is an in-built functionality of the PhysX engine in the first place.