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prometheuspromql

What is the meaning of term "resolution" in prometheus?

In the below promQL query execution:

enter image description here

"Resolution" is mentioned as 14 seconds

and

"total time series" is mentioned as 1

  1. What does "resolution" with value 14 seconds mean?

  2. What is "time series"? What does "time series" with value 1 mean?

  3. What does "load time" indicate?

Solution
    • Resolution is the distance (in time) between points on the graph. 14s was automatically selected based on your query duration (which you've set to 1 hour). This resolution does not necessarily line up with the "real" samples, you can think of it as a sensible interpretation of your data for the given amount of time. For example, I might scrape an application every 60s, and in this case I can still get a point for every 14s via interpolation. The inverse is also true, for queries over a much larger duration (e.g. 1 day), you can have a resolution that is larger than the scrape interval, effectively down-sampling.
    • Time series is a huge topic that you probably just need to google. But to say it briefly, the data you're returning is for only one thing (the "prometheus" job), or in other words, it is a single series of samples across time. If you had 2 jobs, "prometheus" and "foobar", and changed your label matcher to be {job=~".+"}, you would instead return 2 series (one for each label dimension). You would thus have a separate line for "prometheus" and "foobar".
    • Load time is quite simply how long Prometheus took to handle your request.