Arma seems to struggle to handle 4K textures, leading to an eventual freezing of the game, and crash to desktop. It appears to be associated with the amount of virtual memory committed. The game seems to fill up as much VRAM and system RAM as it can, and after a point it starts hitting some limits. I don't see very high page file utilization but paged memory does increase. Notably the system doesn't actually run out of free memory in most cases, and page file doesn't get used by more than ~12%.
This particularly causes an issue with Global Mobilization assets with high texture size and quality. After a prolonged session in the 3DEN editor or if a lot of different assets are used, then the game eventually freezes and FPS falls to <5 fps. The UI is barely responsive. On stable branch this leads to a CTD, on performance/profiling branch this situation gets resolved after several minutes but can reoccur.
Increasing page file (and thus the virtual memory pool) alleviates teh issue to an extent but I'm not sure at what point it will stop occurring.