What you have shown on this image isn’t metrics, what you have shown there is called tracing and while it has some similarities to metrics it is completely different beast. In general there are 3 pillars of the observability:
- Metrics
- Logs
- Traces
Grafana have written nice piece of article to state difference between metrics and logs. The difference between traces and logs is that traces are connected, not only within single instance/request, but though whole life of the request. For example in (distributed) tracing you can check how long the request spent in LB, router, controller, Ecto queue, etc. So while it all seems connected each of the pieces has it’s own place and use case and you should know the difference.
Tracing libraries for Erlang are still in the flux, but I have prepared list of already available tools, feel free to check this out.
