Performance issues with AI pathfinding

Hi guys,

I am currently working on a first person tower defense game. Due to the game style is requires multiple enemies alive at once, however I am running into some frame rate issues as more and more enemies spawn. I have narrowed this down to the pathfinding causing the slow downs. I have tried both Rain AI and Smoothpath but both suffer the same issue. I can only get around 30 enemies before the game becomes unplayable. Does anyone know any ways of optimizing this or a more efficient system to use?

I don’t know much about RainAI or smoothpath, but i have used A* Pathfinding Project

Here is tutorial for how to use astar, and (lucky you) on tower defence game: