Prometheus’s role in observability

Prometheus is objectively pretty great at what it does, but can we make a system fully observable with just Prometheus? Unfortunately, the answer to that question is no. Prometheus’s strength is also its weakness – it’s singularly focused on one thing: metrics.

Prometheus is only focused on the metrics aspect of an observable system. It is purpose-built to efficiently store numeric time series of varying types in a simple format. To the extent to which it interoperates with other observability signals, it is only to provide a link or bridge to some other purpose-built system.

However, Prometheus also provides some of the highest-value data that you can collect. It’s likely your go-to data source in tools such as Grafana to visualize how your systems are performing. Logging and tracing systems can certainly provide more detailed data, but to get them to provide that same level of value in analyzing trends, you...