Prometheus

Prometheus is an open-source monitoring and alerting toolkit originally built at SoundCloud. It collects and stores metrics as time-series data, meaning metrics are stored with a timestamp at which they were recorded, along with optional key-value pairs called labels. Prometheus uses a pull model to scrape metrics from instrumented jobs, either directly or via push gateways for short-lived jobs. It offers a powerful query language (PromQL) to analyze and visualize the collected data, enabling users to set up alerts based on defined thresholds.