I have a few probably related performance issues. I'm testing on Ubuntu 14.04 + Nvidia 331.38 (GTX 770).
The tutorial asked me to run the performance test and after two scenes it hung the game on a black screen for several minutes and I had to restart it.
Performance is pretty bad on the larger simulations, the default simulation is running at 11 FPS. "Jupiters Fly Around the Sun" is 4-5 FPS. Physics Advance is most of the time in the profiler. Pausing the simulation, it does run at 60 FPS and everything looks visually correct.
Opening the galaxy collision simulation always hangs the game.
What's the Linux version doing as far as OpenCL support? I know OpenCL support is not very good on Linux, but it is available in some for or another for the proprietary drivers and Intel's driver. Are there additional steps needed to enable it in Universe Sandbox?
Edit: I left it running longer and eventually the galaxy collision simulation does load, but it's at least 5 minutes.