I found this thread searching answers to how to regard Stats for Texture and Primitives, specifically “Fully Loaded Memory” in the former and “Size” in the latter. It’s the distinction between system and GPU memory I’m trying to understand. dacster13 suggests UE4 refers to system RAM, so I’d add the Size of all meshes and Fully Loaded Memory of all textures to weigh that against system memory. I then also have a question about how polycount and size/number of texture maps relates to video RAM, but firstly; I’ve got 16 GB RAM (system), and with nothing else running but Editor I’d expect to be able to use at least 12 GB of that (notwithstanding the fact that Windows 10’s memory management uses all the memory, but manages what to spend it on depending on what’s most important, what’s “on top”.) So, my Stats report I’m loading about 5 GB total between geometry and texture, mainly geometry, and this between two levels created under Persistent. I’ve yet to create load and unloads to leverage Level Streaming Volumes, which is really what I’m after to understand how to right-size each Streaming Level.
So, with 16 GB RAM why would UE4 crash with an out of memory message? I have BTW the GTX 980 Ti with 6 GB video RAM, which makes me suspect I’m right up against that threshold. This leads back to my second question about video RAM. My understanding is that the GPU is only called on to draw to the screen whatever draw calls direct it to do so, this hinging on what’s in front of the camera. I’ve optimized my set with many small chunks to leverage occlusion culling, am getting 70-90 fps depending on which way the camera is facing, but GPU doesn’t feel pushed at all. That said, when I open a utility like TechPower to monitor GPU memory usage I see all 5.5 GB loaded into video memory. How to square that with dacster13’s statement? Is it possible that both types of memory are loaded with X?