UE 5.4 World partitioned NavMesh

Development Programming & Scripting
1

I am not sure if this is a bug or intended feature on the WP-NavMesh, since it still marked as Experimental.

So, I have big world that being setup using World Partition, and obviously I need NavMesh for the enemy AI. Currently, the NavMesh Runtime Generation is set to STATIC, and I already make sure all the settings on each worls is correct.

However, am seeing a memory allocation of 100x the actual NavMesh, everytime I open a level (e.g., there is 3.4GB allocation, while the actual navmesh is only 39MB). The memory allocation is freed on the next 1-3mins by auto GC (manually calling CollectGC using blueprint doesn’t seem to do anything).

I tried to debug it using visual studio and Unreal Insight, and I just can’t believe NavMeshRecast actually allocate that HUGE MEMORY! why do this need 3.4GB of memory?? that doesn’t make any sense.

maybe anyone know about this and want to share? This additional 3.4GB on every load map is ridicolous! Am targetting player with memory below 12GB (the initial plan was 8GB, but the spike on load is not something I can control)

2

For anyone who face the same problem, just move to the dynamic generation. After a deep debugging, I found that a lot of memory allocation on NavmeshRecast didn’t get freed until the AutoGC event (even calling Garbage Collect didn’t help). Hopefully this issue will be addressed and fixed soon.

Note: don’t forget to delete the baked navigation on your world and unchecked the “strictly static” navigation on world settings.