Minecraft Lagging in 1.8 snapshots higher than 14w02b, but not in 1.7

So, some people in 1.8 snapshots(like me) are experiencing some weird lag that is almost non-fixable, but in 1.7 the game works perfectly fine, Clearing some space, updating Java, changing the amount of RAM doesn't change anything. I personally have also lag in the options menu too(When I go in it, the game freezes)... This(Lag) doesn't happen in the 14w02b or lower snapshots though. Could it be something added in the code in 14w02c that made some people get lag? Please fix this! (or maybe tell how to fix it if it isn't the snapshot)

Thank You for reading this.
These are some wierd warnings I get in the launcher when I enter a world.