Prometheus is an open-source systems monitoring and alerting toolkit. Its main features are:

* a multi-dimensional data model with time series data identified by metric name and key/value pairs
* PromQL, a flexible query language to leverage this dimensionality
* no reliance on distributed storage; single server nodes are autonomous
* time series collection happens via a pull model over HTTP
* pushing time series is supported via an intermediary gateway
* targets are discovered via service discovery or static configuration
* multiple modes of graphing and dashboarding support