Prometheus
In depthMonitoring
Open-source monitoring and alerting system that scrapes metrics and stores them as time series.
Prometheus, explained
Written by EduVerseWhat it is
Prometheus is an open-source monitoring system that tracks numbers about your systems over time, such as request counts, memory use or queue length. At a fixed interval it pulls these metrics from an HTTP endpoint on each service, stores them as time series and lets you query them with its own language, PromQL.
Why teams use it
Logs tell you what happened to one request; metrics show how the whole system behaves. Prometheus is simple to run, fits naturally with Kubernetes and, together with Alertmanager, warns you when a value crosses a limit. It’s usually paired with Grafana, because its own UI is quite basic.
An example from work
You add a new Spring Boot service to the scrape config, but on the Prometheus Targets page it shows as DOWN with a 404. The config points at /metrics, while Spring Boot Actuator exposes its metrics at /actuator/prometheus, so you change metrics_path and the target turns UP.
Our own explanation, not a quote from the book.
In the book
Sentences from The Software Realm, Decoded that mention Prometheus, exactly as printed.
4 more passages about Prometheus in the full book
Read every conversation where Prometheus comes up, with the interactive slides and demos.
Where it fits
Collecting and storing metrics, alerting
Coverage in the book
Covered in depth: multiple pages with explanations, examples and simulations.
