Fps Glitch In 1.8

Recently i have been playing some of the 1.8 snapshots and I've been only getting 10-25 fps.. When I launched into 1.7 I got about 40-60 fps. I have also noticed sethbling has mentioned in his videos whilst recording 1.8 footage, that he has a fps drop as well. I got a 2 screenshots combined into 1 image comparing f3 mode with 1.8 and 1.7 if that helps. - Cheers, Luke