Please help with optimization?!?!?

Minecraft seems to struggle to run on my laptop and im looking for some more tips to try and make it run better. Me and my friend both have lenovo Y700 gaming laptops and i cant seem to get over 30ish fps while my friend can get around 90ish on higher settings than me with our same laptops. ive been trying to fix this for a while and ive tried everything i could find online and from my friends. I have dedicated 4 and 8 gigs of ram to the game as well as installed optifine and made sure it was using the gpu rather than internal graphics and i still cant get any better framerate. ive noticed that task manager has java using around 5 gigs of ram but in game it only tells me im using a little over 1 gig. i dont know if that is of any significance and i cant find out a way to determine what is using the rest of the ram or how to stop it. please help out if you know anything i have been struggling to find a fix for a long time.