Derived Metrics

Beta

Derived metrics are in beta, on paid plans. Limits are subject to change.

A derived metric counts or measures records as they arrive and writes the result as a real metric: error logs per service per minute, the p95 of a span's duration, revenue summed from checkout events. Once written, it's a metric like any you send over OpenTelemetry. Chart it under Metrics, put it on a dashboard, and alert on it with a telemetry monitor.

Querying a metric is far cheaper than scanning raw logs, so a derived metric is the right home for anything you look at often or keep for longer.

Create one

Open Manage Streams, pick a Stream and go to Derived Metrics → New Metric. As you edit, the preview shows the series it would write over the last hours, from your real data, before anything is saved.

Setting
Metric name	How it appears in Metrics, charts and monitors, e.g. checkout.errors. It can't be renamed later.
From	Logs or traces (OpenTelemetry Streams), or events (Events Streams), and a search choosing which records count.
Measure	See the table below.
One series per	Up to four fields; each becomes a tag on the metric.
Bucket	10 seconds to 1 hour per point.
Lag	Stay this far behind now so late records land first (default 60 s).
Run every	How often it catches up (the plan sets a 1 minute floor).
Backfill	Hours of history to write when it's created (up to 7 days).

Measure	Writes	Read it as
Count	a counter of matching records	increase or rate
Sum of a field	a counter	increase or rate
Distribution of a field	a histogram	p50 to p99, avg, count
Average, Min, Max of a field	a gauge	avg, min, max

RED metrics

An OpenTelemetry Stream can add the three standard service metrics in one click, Add RED Metrics: requests, errors and duration from server spans, per service and operation.

Keeping it right

• Each metric shows how far behind now it is and its last run. Expand it for the run log and live runs.
• Run Now catches up straight away instead of waiting for the next run.
• Changing what a metric measures (its search, measure, grouping or bucket) rebuilds it: the points it wrote are replaced from the backfill point. Rebuild does the same on demand.
• Runs are safe to repeat: a retried or overlapping run never counts a record twice.
• Delete removes the points it wrote.

Limits

Plan	Derived metrics
Hobby	5
Pro, Founders	25
Team	200
Enterprise	1,000

API

GET /v1/telemetry/derivedMetrics	List a namespace's (or a Stream's) derived metrics
POST /v1/telemetry/derivedMetrics/create, /update, /delete	Manage them
POST /v1/telemetry/derivedMetrics/preview	The series a definition would write, without saving
POST /v1/telemetry/derivedMetrics/runNow, /rebuild	Catch up now, or rewrite from a point
GET /v1/telemetry/derivedMetrics/runs	Its materialization runs
POST /v1/telemetry/derivedMetrics/red	Add the RED metrics to an OpenTelemetry Stream