Struggling to find source of lag/hitching/stuttering

The video demonstrates exactly what’s happening, I start my level, everything is fine, 70-90fps and after about 30 seconds my game starts to hitch and stutter. It’s hard for me to understand how to profile an issue like this, I have smooth frame rate to false, brutal LODs and culling distances, the shader complexity for the assets are average. I would argue that the level is pretty optimized. Any help would be greatly appreciated!

Here is another instance of the same issue, different map/assets with no materials applied… - YouTube

It’s kinda hard to tell actually from your video, it’s probably much more noticeable when playing.

I always find the best approach for stuff like this it to chop out vast portions of the game and see what happens. If it works the chunk you just axed has the problem. Then go from there. Surprisingly quick sometimes.

It does seem like you tackled most of the obvious issues, could it be something to do with your player?

I had this issue too, basically through the process of elimination I narrowed it down to my character class, and from there found out it was caused by setting morph target values many times every frame. Never had an issue with it before until 4.22, but I fixed it by buffering out the timing using a delay.

No idea what it may be for you but, you can use profilegpuhitches command to record when the hitches happen in the editor and when you stop playing you can see in the profiler what is costing the most time. I tried this myself and it pointed to hzb(mip=1) 512x256 or something and it didnt really help me out, but it might for you.