Poor physics performance on low-end devices?

I have a Galaxy S3 Mini, a one year old device, I've just done the Wheel Collider sample from the upgrade documentation and built to the device. I have a single vehicle with a couple of bouncing spheres in a scene, a mesh collider for a single track and I'm getting a pretty low frame rate. I set the Fixed Time Step to 0.04 and set all the Android optimisations on for Unity 5, but the framerate is terrible?

I'm guessing Physics and Low-end devices are a no-no? And will be for quite some time still?
An iPhone 4 would have similar issues, being CPU bound...

I guess I was magically hoping for PhysX 3.x to just work smoothly on low-end devices

 

Have you profiled to prove the issue is PhysX?

I have 12 cars with 4 wheels each, a mesh collider track and terrain, 100 capsule colliders for trees, and a few others for some extra pieces...running on iPad 2 at perfect speed, I hate to say it but it may be something you're doing wrong. Even on my old Astro Cyclone (the worst android I could find!) I get a reasonable 20 fps!

 

Yes, it's purely physics performance.

An iPad 2 has a lot more processing power than an entry level Android phone.
I don't have any issues on the iPad 2.

 

@Jonny Roy
Can you PM me a link to an APK, or a store link so I can test your app on my device?

 

http://forum.unity3d.com/threads/official-5-0-feedback-request-for-physx.283236/#post-1879086

 

Sorry can't share my APK at the moment, there's a few things in the game I'm not ready to share yet. But based on what you have said it would suggest it's a PhysX issue, 1 GHz dual-core Cortex-A9 which mine is a ARM Cortex A8 1.2GHz (single core) so it might be a bug specific to the Cortex-A9 or a profiler issue.

As you're is just a basic test scene, why not share the Unity Project, I have 3 android devices, 2 very low spec, 1 pretty high, be happy to confirm so we could submit a bug report. Also, which Beta did you test with? Just in case we're on different versions (last test was Beta 15, Beta 16 is broken deploying to my device :S)

 

FYI, iPad 2 and Galaxy S3 Mini have the same CPU, so it is strange to see a difference! It would suggest a bug if the same project is that much worst!

 

Hey @Jonny Roy and @Meltdown, as a fellow android dev i hope you guys can coordinate to file a bug report, and let us know the results here! I'd be happy to help but i only have two high-end devices available at the moment.

 

I'm not sure what happened, but I re-created the scene and the project, and now I get a smooth 28-30 FPS on my phone???

Not sure if something somehow got corrupt, but anyway, I will take it

Sorry for the inconvenience.

 

Excellent! No need to apologise. I'm glad you raised it and that it turned out to be something silly. I've actually had a weird bug where on a project I upgraded (I've upgraded since 4.3 - 5.16 with each beta) it runs on Blackberry for 20 seconds then crashes...yet if I copy all the files to a new project it's fine! Strange things are there to test us!

Let me know if you need anything checking on low end devices I'll be happy to help.

 

Yeah funny though, in this new test scene, I was getting a few crash bugs, and sometimes the scene loaded and everything seemed very jittery, as if the physics wasn't sure what it was doing. Restarting the app seemed to work though.

If I keep getting it I'll log a bug.
This is all using Beta 16.