Avolanty is referring to my ocean project on the forums, and I also have the same issue. I start out at ~650mb with my project (Download below) and it slowly rises as I am editing blueprints/materials etc. I usually restart the editor once it gets up to 2.5gb or more to flush the data out, but would be nice to know whether I am doing something wrong or what else might be happening.
Here is the Project:
and here is my DxDiag - [Link][1]
Thanks