A couple of weeks back, I noticed my game stuttering and the experience got progressively worse the longer I played. 

I opened the Resource Monitor to find the game eating up copious amounts of my RAM.

I noticed it in one world at first, but it seems to affect all the worlds I have played since.

Here is the RAM usage sitting on the start screen, before opening any worlds:

Now after starting the world and flying around spawn for about 2 to 3 minutes.

And then, once I've closed the world, the game doesn't really free up that RAM. It holds on to most of it.

Here are my PC specs:

I have also linked the .MCWORLD file here so you can take a look at it. I did use a WorldEdit clone add-on previously to do some terrain work. I do not have it activated or included anymore. I did have to turn on "Use Beta API's" to use the add-on, so that's the only experimental feature activated for this world.

Click to download world

I've worked on this world for months, and now I'm worried that all that effort will be for naught. I'm hoping we can find a solution to this problem.