[0.15.2] Frame rate drops to half

[weeman]

Hi,

since factorio 0.15 I can play the game fine for some minutes at smooth 60 FPS.
Then the frame rate drops to exactly 30 FPS.
Restarting the game brings the frame rate back to 60 FPS for some minutes again.

I looked at the known and reported bugs but didn't find a similar problem.
With 0.14 everything was fine.

My system:
- Core i7
- Intel HD520
- Ubuntu 17.04

If I can provide any helping information (debug mode, debug logs etc..) please let me know how to do.

Thanks

[Loewchen]

Post your log, see my signature.