Prometheus
The leading open-source monitoring system and time-series database for metrics.
Definition
Prometheus is an open-source monitoring system and time-series database originally developed at SoundCloud and donated to the CNCF in 2016. It uses a pull-based scrape model, a multi-dimensional data model with labels, and PromQL for querying. It is the de facto standard for Kubernetes metrics.
In depth
Prometheus scrapes metrics from instrumented applications and infrastructure components at regular intervals, storing the data as time series identified by metric name and key-value label pairs. Its ecosystem includes hundreds of exporters covering virtually every system from Linux hosts to PostgreSQL to Redis. Alertmanager handles routing, deduplication, and silencing of alerts generated by Prometheus rules. While Prometheus itself is designed for short-to-medium-term storage and single-cluster deployments, tools like Thanos or Cortex (and hosted platforms like obseria.io) extend it for long-term storage and multi-cluster federation. obseria.io is fully PromQL-compatible and accepts Prometheus remote_write, making migration seamless.
Related terms
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