In Grafana Explore, or by editing any visualizations on any Dashboard, you can display the top reported metrics using the following PromQL Query:

topk(10, count by (__name__)({__name__=~".+"}))

This query finds the 10 metrics with the highest cardinality.

If you want, you can track more labels like this:

topk(10, count by (__name__, component)({__name__=~".+"}))

Next, change the query Type to Instant. Your metrics cardinalities are likely not changing over time, so we just need a snapshot of the current counts, and not a graph of metrics and their cardinalities over time.

When you’re done, click Run query in the top right corner of your screen. You should see the a table with metrics and their corresponding cardinalities

From here, you can query any individual high-cardinality metric to drill down into all its different permutations.

For example, the apiserver_request_duration_seconds_bucket metric on my cluster had >6k different label combinations, some of them where not interesting and where dropped at scrape time on Prometheus side.

NOTE: Ensure that query Type is still set to Instant or your query may time out.

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