FPS changes dramatically depending on if you look up or down. This does not happen on normal worlds, mainly on Superflat worlds. But it is really bad on the Void preset.

Steps to reproduce:

1. Create a Superflat Void World
2. Press F3 + Shift + Alt
3. Look Down and enjoy the high FPS Counter
4. Look Up and be amazed

Observed Result

Looking up destroys all your FPS.

Expected Result

FPS should not be affected as much.