add a optional limit on number of npcs per scene default = 40

bin/OpenSimDefaults.ini

@@ -2142,6 +2142,12 @@
 [NPC]
     ;; Enable Non Player Character (NPC) facilities
     Enabled = false
+
+    ;; max number of NPCs per scene default: 40
+    ;; set to a negative value to allow any number
+    ;; note that a NPC is almost as heavy as a normal avatar, so you should limit them
+    ;; MaxNumberNPCsPerScene = 40
+
     ;; several options to control NPCs creation
 
     ;; allow NPCs to be created not Owned {true false} default: true