What a DPS is made of
A DPS is edited in four sections, always applied in the same order:
| Section (in the edit form) | What it defines |
|---|---|
| Metric selector | Which agents/metrics to include: an agent regexp (or a picked agent), an optional environment override, and a metric name regexp. |
| Metric type selector | Which raw field of the metric becomes “the value” of each point (AVG / MAX / MIN / COUNT), whether to keep effective (non-zero-count) points only, and an optional pinned time period selector. |
| Values filtering | An optional operator (equal to / greater than / … / between / first / last) that keeps only the raw points matching a condition, applied before reducing and resampling. |
| Reduce | How the filtered points are combined into the final result: scope (one value / one value per series / one merged series) and function (average / max / min / count / first / last / plateau) — plus an optional resample target point count, applied after reduce, to bucket down whatever time series survives (only relevant when no reduce is configured, or scope is One serie; scopes One/One per series already collapse to a single value, so resample has no effect there). |
Why filter before reduce, not after: the value filter operates on individual raw points (that’s what makes it a Data Point Selector), and two of its operators — first / last — only make sense applied to raw points, not to an already-reduced single value. The edit form’s own section order (Values filtering before Reduce) reflects this.
Result shapes
The reduce scope determines the shape of the result:
| Scope | Result kind | Shape |
|---|---|---|
| One | Single value | One number, computed from every matched point across every series flattened together. |
| One per series | Per-series values | One number per matched series (e.g. one per agent/metric pair). |
| One serie | Merged series | One merged time series: one point per distinct timestamp seen across the input series. |
If no reduce scope/function is configured, the DPS returns its raw, filtered, resampled series (one series per matched agent/metric, each with its own list of points) instead of a reduced result.
See Metric type selector, Values filtering, Reduce and Resample for worked examples of each stage, and the full worked example for the whole pipeline end to end.