Really bad constant stuttering in game

Game Modding | Call of Duty: Black Ops 3 | Radiant

blink-420:

I’m having a problem with performance on my map. It is a large map with lots of detail which could definitely be a factor. But last time I played on the map it had no performance issues but after compiling the map it is now getting really bad constant stuttering in the FPS right at the start. The only changes I made since it was last running fine was me adjusting some clip brush models. Any suggestions ??