FastAPI instrumentation only publishes an OTEL histogram for HTTP metrics

[nabheet]

FastAPI instrumentation only publishes an OTEL histogram for HTTP metrics instead of also publishing the raw request duration. I understand that the histogram is efficient and helpful but I was wondering it could/should also publish the raw time taken for each route.

I am not sure I understand OTEL histograms. So looking for some ideas on how to get raw request duration.

I guess I could get it from spans also but they are not stored in our Prometheus instance so Grafana can't query them.

Also, I just discovered this thing called Span Metrics Connector - could this be a better option to generate raw duration per route instead of having the FastAPI OTEL middleware generate this metric?

Or I could use some advice on how to display OTEL FastAPI histogram metrics stored in Prometheus. I am having difficulty displaying routes on the x-axis and corresponding time taken on the y-axis with the x-axis being sorted by time taken. I am ending up with this ...

The time buckets are on the x-axis and count on the y-axis.

Or I end up with this, where I can't sort by duration: