I have this world since 1.7.0 and backed it up all the way to 1.13.2. I've been waiting a lot for 1.14 to come out and I finally did the back up and so far the chunk loading is extremely slow.

What I expected to happen was...: 

I expected to have a fully functioning world with little to no lag after a day of being up like 1.7 - 1.13.2 did for a very long while.

What actually happened was...:

What happened is I get below 20 fps when I move and 60 fps when I am on the pause screen. The chunks CONSTANTLY refresh (ever under my own feet) and it's really annoying to see the other end of the world when there should be a giant mountain blocking me from seeing that.

Steps to Reproduce:
1. Running to places or moving my whole character in general
2. Fast flying in creative or flying in general
3. Swimming or in a cave system mining