Metric types.
also: counter metric · histogram metric · histogram metrics · gauge metric · counter metricsCounters only go up, gauges go up and down, histograms bucket observations such as latencies, and summaries precompute quantiles.
the two-minute refresher
- Counter: requests_total; graph rate(requests_total[5m]) for requests per second.
- Gauge: queue_depth, active_connections, the current state.
- Histogram: request_duration_seconds buckets; histogram_quantile(0.99, …) gives P99.
- Prefer histograms to summaries: summaries can't be aggregated across instances.