Thank you @mprudek, I’ll definitely have a look at version 2.0, but that will have to wait. Storing the downsampled data in a separate table was one thing I was thinking of, but then I’d lose the nice property of all the data being in one database and accessible through the same grafana display.
@maneth You made my day! After disabling monitoring and drop database _internal, influxdb went from 150 MB to 30 MB of RAM! And CPU load also nicely decreased. I have free RAM, hooray!