High Index Buffer Memory

After some time in the editor my index buffer memory slowly climbs causing my memory (top right) to climb as well.
How can I fix this? I do not even know what index buffer memory is and google/UE4 manual isn’t mentioning this.
When I start the project it starts at ~20mb but as you can see in the screenshot it is now at 1gb and the more I use the editor the more it increases.

Any help would be appreciated. If you have any questions I will answer.

I’d have some issued with Index/Vertex buffer memory as well. I can’t confirm this, but I do believe that having vertex painted instances will increase the Index/Vertex buffer by x how many times you have painted that specific mesh.

For example, if you have a 50k vertices rock, and you have 100 hand-painted vertex painted rocks, you will have whatever memory is used for those 50k vertices multiplied by x100, that is the count of hand-painted rocks that you have.

I do believe that it’s better, especially for large open-world scenes not to hand-paint static meshes.

PS: I don’t believe it might be the case for you scene, but I do believe that the problem is real, and that we should be able to pinpoint exact Vertex/Index buffer usage.