This is a very short post to show one of my favorite system monitoring tools: NetHogs. If you are on a Linux box, it should be fairly easy to get it no matter what is your Linux distribution.
Once you have it, just run it as root and you will have a minimalistic, readable, and very useful list of which processes are consuming your bandwidth and how much of it each process is using.
You can also run it with the
-v1 flag to get the sum of KB instead of the
KB/s rate of each process.