Hi @jcasals,
As promised I’ve updated the docs for the statistics tool. I hope that the explanations of the returned values are a bit clearer now: The cta-statistics-update tool - EOSCTA Docs
But as mentioned, we really recommend you base your statistics gathering and monitoring on the output of cta-admin --json ta ls --all instead of using the output of cta-statistics-save, especially if you’re setting up something new. The tape ls output is much more flexible and allows you to create more interesting plots/dashboards.
We’re not using statistics-save anymore ourselves, but we do (as should you, once it is fixed) use the cta-statistics-update command to update the statistics for recently written tapes.