I'm making a standard 9x9x5 zombie spawner and there are numerous tutorials out there. I'm trying to figure out for myself how to improve the efficiency, because I feel something is wrong with my design.
When mobs are spawned, how far from the spawner do they need to go before the spawner can spawn again? According to wiki:
If, at the time of spawning, 6 or more mobs of the spawner's type are present within a 9×9×9 area, centered on the spawner block, the spawner "poofs" without creating any mobs and then waits for the next cycle.
Does that mean mobs must be just outside the 9x9 room?
This is how the tunnel looks like, which is supposed to get the mobs out as soon as possible:
However I don't think it is working properly, because the zombies bunch up too much, and the little zombies block the elevator.