NetHogs is a small "net top" tool.
Instead of breaking the traffic down per protocol or per subnet, like
most such tools do, it groups bandwidth by process and does not rely
on a special kernel module to be loaded.
So if there's suddenly a lot of network traffic, you can fire up
NetHogs and immediately see which PID is causing this, and if it's
some kind of spinning process, kill it.
|nethogs||Net top tool grouping bandwidth per process|