Ubuntu mining. How to tell which miner is dead, and kill the process?

[chungenhung]

So I know I can run each miner in different "screen", so I can switch between then to check the status by reattaching to the "screen".
Now, say miner3 hangs, how would I know which one it is to kill in the process and start again? Wouldn't all appear at Phoenix.py? how to distinguish which is which?

thanks