emonPi Network Data Consumption

I have been experimenting running an emonPi using a GSM 3G data connection. The emonPi supports Hi-Link USB 3G modems, however it’s not something I’ve used much myself.

I setup a test overnight posting a couple of empty (zeros) feeds to emoncms.org. I was surprised after 24hrs to see the modem had reported 28Mb down and 11Mb up = total 45Mb per day. This seem a bit high for posting a couple of zeros! This would equate to about 1.4Gb per month.

Looking at the Emoncms WiFi stats page for my home emonPi (connected via Wifi) it shows a data consumption of Rx: 980Mb and Tx: 552Mb over 6 days which equates to 255Mb per day or 3GB per month. This emonPi is posting 10’s of feeds to Emoncms.org and running openHAB and nodeRED which used to control my home automation system. However, this is still higher than I was expecting.

Has anyone recorded the data consumption of a RaspberryPi / emonPi? How would we go about trying to work out what processes are using the data? Could there be background Linux processes using data?

Is the reporting accurate? The Emoncms WiFi page gets it’s data from ifconfig