* Add anchored and smoothed to vector selectors.
This adds "anchored" and "smoothed" keywords that can be used following a matrix selector.
"Anchored" selects the last point before the range (or the first one after the range) and adds it at the boundary of the matrix selector.
"Smoothed" applies linear interpolation at the edges using the points around the edges. In the absence of a point before or after the edge, the first or the last point is added to the edge, without interpolation.
*Exemple usage*
* `increase(caddy_http_requests_total[5m] anchored)` (equivalent of *caddy_http_requests_total - caddy_http_requests_total offset 5m* but takes counter reset into consideration)
* `rate(caddy_http_requests_total[step()] smoothed)`
Signed-off-by: Julien Pivotto <291750+roidelapluie@users.noreply.github.com>
* Update docs/feature_flags.md
Co-authored-by: Charles Korn <charleskorn@users.noreply.github.com>
Signed-off-by: Julien <291750+roidelapluie@users.noreply.github.com>
* Smoothed/Anchored rate: Add more tests
Signed-off-by: Julien Pivotto <291750+roidelapluie@users.noreply.github.com>
* Anchored/Smoothed modifier: error out with histograms
Signed-off-by: Julien Pivotto <291750+roidelapluie@users.noreply.github.com>
---------
Signed-off-by: Julien Pivotto <291750+roidelapluie@users.noreply.github.com>
Signed-off-by: Julien <291750+roidelapluie@users.noreply.github.com>
Co-authored-by: Charles Korn <charleskorn@users.noreply.github.com>
So far, we emitted a `HistogramCounterResetCollisionWarning` when
encountering conflicting counter resets in the calculation of (i)rate
and friends. We even tested for that. However, in the rate
calculation, we are not interested in those collisions. They are
actually expected.
On the other hand, we did not warn about those collisions when doing a
`sum` aggregation, where such a warning would be appropriate.
This commit removes the warning in the former case and adds it in the
latter. Sadly, we cannot really test this as we still remove the
counter reset hint for the first sample in a chunk. (And that's the
only sample where we could get a `NotCounterReset` hint.)
Signed-off-by: beorn7 <beorn@grafana.com>
