Prometheus

Prometheus collects metrics from configured targets at given intervals, evaluates rule expressions against them, displays the results and triggers alerts when conditions are observed. It is a Cloud Native Computing Foundation project and a common base layer for infrastructure monitoring.

What sets it apart is a multi-dimensional data model, where a time series is identified by a metric name plus a set of key and value dimensions. PromQL exists to exploit that dimensionality, letting you slice series along labels instead of querying flat names.

Several architectural decisions shape how it gets deployed.

• Pull model: the server scrapes targets over HTTP rather than waiting for them to report.
• Autonomous nodes: a single server needs no distributed storage to stay useful.
• Service discovery: targets arrive from discovery mechanisms or from static configuration.
• Push gateway: batch jobs too short-lived to scrape push through an intermediary instead.
• Federation: hierarchical and horizontal federation links servers into larger topologies.

Installation runs from precompiled binaries, which the project recommends, or Docker images on Quay and Docker Hub. Building from source needs Go, NodeJS and npm, and the Makefile carries targets for building, testing, formatting and compiling the React interface, producing both the server and the promtool binary.