[Alpha 8 build 2083]
Starting at about the 1 hour mark in my most recent game I had enough fence made to completely fence in my little village because I was mostly building underground. After I finished placing the last piece of the fence to completely close off my area for each goblin trying to get to the stockpile the % of my cpu used by the pathfinder script went up about 15%. If I went and killed all the goblins or I made an opening in the fence that the goblins could come through the Pathfinding script dropped to regular usage.
Saving and reloading doesn’t work as for some reason when you do that even after you kill all the goblins in the area and all your villagers are standing around idle the pathfinder is still stuck in its wigged out state, and in some cases if you save right after you killed the last goblin when you reload you come back to more goblins having spawned.
Sorry if this is in the wrong place.
I fenced off my little town area, because, why not. I thought it would help with goblin raids.
Well, it stopped goblins from moving all together. I didn’t notice this till much later when I noticed things seemed to be lagging. That is when I realized that they were just spawning in the same place. There were tons of goblins all above their pit at their spawn.
That camp would be impossible to take out with how many were spawned there.
hey there @arrakisdef … welcome aboard! 
I am pretty sure there’s another report like this (its a known issue about walling in your town), but this is the first report I could find to merge with yours… 