Many people have been getting better frames in the new update, but for some the Fps plumited. In this video it is a simple very fast fix to fixing not only lag spikes, but a 60 Fps cap some people faced. If you cant watch I will sum it up here. Basically when you are on the launcher screen click edit profile. Find JVM arguments and check the box near it. Inside will be a bunch of gobblygook. Erase out everything, but make sure to keep -Xmx1G. That is it tada! To boost yourself even more replace the 1 with a higher number. The number has to be lower than the ram your computer has available. So say you have 6G of ram, you would put -Xmx3G (I would reccomend keeping it lower than half). Have fun playing the new update!