grafana - How to calculate time a metric is above a specific value with Prometheus?

Question

I m a beginner with Prometheus and looking for some help for a query (seems basic but I m struggling to find the right syntax).

I have a metric called "speed" that return the speed of a probe (in km/h). I'd like to calculate how much time the driver has spent driving over the speed of 50km/h (speed limit) during the last - let's say - 60 minutes. And potentially also between a specific range of speed (e.g: 40 to 50).

I'm attaching a Grafana chart to illustrate it - I'm looking to calculate how much time a driver has spent in this zone.

Thank you

Answer 1

Try the following query:

avg_over_time((speed > bool 50)[1h:]) * 60

Here you'll find more details about this query which uses the bool modifier and the subquery support.