Michael Hoffmann d6d9f97bac
promql: histogram_fraction for bucket histograms (#16095)
* promql: histogram_fraction for bucket histograms

This PR extends the histogram_fraction function to also work with classic bucket histograms. This is beneficial because it allows expressions like sum(increase(my_bucket{le="0.5"}[10m]))/sum(increase(my_total[10m])) to be written without knowing the actual values of the "le" label, easing the transition to native histograms later on.
It also feels natural since histogram_quantile also can deal with classic histograms.

Signed-off-by: Michael Hoffmann <mhoffmann@cloudflare.com>

* promql: histogram_fraction for bucket histograms

* Add documentation and reduce code duplication
* Fix a bug in linear interpolation between bucket boundaries
* Add more PromQL tests

Signed-off-by: Michael Hoffmann <mhoffmann@cloudflare.com>

* Update docs/querying/functions.md

Co-authored-by: Björn Rabenstein <github@rabenste.in>
Signed-off-by: Michael Hoffmann <mhoffm@posteo.de>

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Signed-off-by: Michael Hoffmann <mhoffmann@cloudflare.com>
Signed-off-by: Michael Hoffmann <mhoffm@posteo.de>
Co-authored-by: Björn Rabenstein <github@rabenste.in>
2025-04-23 00:28:31 +02:00
..
2025-02-28 11:24:25 +11:00