Save GSM data using mDash + mongooso os


I just connected Mongoose os with mDash using GSM network and I have question how I configure mDash to save transactions data ?

When I disable mDash my app use about 40kB per h but when I enable mDash it’s rise to 200kB

Where are you trying to save it? mDash database?
I use the mgos_dash_notifyf function

Are you saying 200kb is too large for your device?

I believe you’re trying to reduce your traffic over GSM network, not save a file, correct?

If so - you’ve discovered that mDash is not very efficient when it comes to bandwidth usage. It’s pretty chatty and in no way optimized for wireless use. mDash uses WebSockets to sync devices with the server. Once a WebSocket connection is opened, ping-pong keepalive traffic is sent back and forth between each device and the mDash server. By default, this happens every 15 seconds and the WS ping-pong message size is 80 bytes.

This handy post describes the WebSocket + TCP overhead for every transmission. If you have an idle device that is completely static, mDash will use 62.8KB of data per hour (in aggregate for both directions) in my experience. Of course any device activity, shadow updates, etc. will add on top of this.

As for how to reduce the bandwidth, this is something only Cesanta can address.

Hope this helps,