Anyone datalogging?

[shark24]

I do not say pi is useless but the plotter part with opencpn. For charts I use mainly verbergen paper charts. And OSM. Behind Budapest there are not enough water petrol stations. Also the Marina situation is more difficult. And this means you need to walk with 2 20l (Kanister) to take Diesel. And this is the key point to find the most close stations to the river. And in such areas Internet is also not obligate. It's a main part of around 500 km.

Yes I am aware of the problem with the gas station. That's why I've already recommended you in another thread to get the free osm maps on your phone. I guess its easier to carry your phone with you than your pi when you need to find the way. I always took a portable dolly with me so I wouldn't have to carry the fuel. Thanks to the navigator app I always found the way to the gas station and back to my boat even without internet.

The trackball I mean no hardware.  I mean you touch screen somewhere  on display and get a menu with big areas to touch and that you can free define in front.

Ok I've misunderstood you there. For node red dashboard you can create such a menu with the template node.

Question is data logging and this not for a little time. and if he does go for sensors not just for a week or so on his testing and developement database special the logging of IOT data like sensors for a later review and sort things out he should compare in general why and what he is doing in comparison influxdb and mysql.

I hope this article helps to understand:

https://db-engines.com/de/blog_post/71

i think for the moment i leave a bit the sql sector shark did told his needs are mainly to have at a time a special information and time periods are not interesting for him. I am with data logging more interest in time periods to analyse. I think if you log a long time and keep the actual data in a array and look than in reviews for a time period say one or 2 years you will see how is the performance. For checking and lookig for servers i long time use nagios. I see in influx and grafana for our needs more advantages. If he will use Telegraph as collector on a third pc than he will see that mysql or the light version needs much more resources over the time.

I'm aware of the concept of time series databases. Our boats aren't exactly like the Queen Mary 2 so we won't produce terabytes of data. From my point of view most of the databases you can run on the pi like mysql, influxdb, etc. are slowing down the system. That's why I prefer rather logging data to a file/sqlite than having a database server in the background bothering my cpu. Certainly the data queries will take longer but my pi isn't kept busy constantly. I don't know why you would need two years of sensor data on your pi and why you need a good performance for the data analysis. And even if you want time series data of a long range for a graph it'll be one slow select query and that's it. The select query takes 80 instead of 10 milliseconds - pardon my French but I don't give a rat's ***. I won't sacrifice over all system performance for two or three slow queries it takes to get the  some data from bigger ranged time series.   
If you want to use openplotter and the pi for real time data analysis of big time series maybe you got the wrong software and hardware.