There are lots of answers that show how to monitor network usage in Ubuntu 16.04, even per process using the nethogs
package. However, my complaint with all those methods is that they are all command line, and require a terminal to remain open on my system doing the monitoring. Then there is also the total network usage in the System Monitor, but that is not per process.
Is there a way I can append another column to the System Monitor that will show me the total (cumulative) data used by each process since last reboot? Something similar to the Memory, or CPU used by a process, but for Internet data.