Way to much lag in preformance/frames with Worlds (big issue)

I don't know what happened after the aquatic update, but it's horrendous. Chunks take over 5 seconds to load, walls sometimes randomly become invisible, blocks get mined only to pop back into existence, placed blocks suddenly vanish without getting put back in my inventory, and multiple arrows disappear only to reappear 5 seconds later all at once. It's making the game nearly unplayable. I even set the Simulation Distance, Render Distance, and particle distance to minimum and it doesn't help. What is going on, and how long will it take to patch?

EDIT: This is all solo survival mode, btw. I'm not talking about internet lag.