Home / Definitions / Prometheus


Ali Azhar
Last Updated October 25, 2021 5:30 am

Prometheus software is an open-source application for system monitoring and alerting of hardware and kernel-related metrics. It helps users understand the state and trajectory of their systems. For example, web server users can monitor the number of active connections or the number of active queries in the system. 

Prometheus offers a multidimensional data model with time series, real-time alerting, and flexible queries. The components of Prometheus include the main Prometheus server that stores data, client libraries for the application code, an alert manager, exporters for services like Graphite, StatsD, etc., and a push gateway for supporting short-lived jobs. Prometheus was originally built at SoundCloud. It is able to integrate with several applications, such as Asana or NetBox, either natively or through a plug-in. 

How does Prometheus software work?

Prometheus gathers the metrics such as time-series data from an exposed HTTP endpoint. After gathering the data, Prometheus stores the data in the form of time series in a local database. It can also integrate with a cloud or remote database for storage. Apart from storing the time series data, Prometheus can be used to generate queries to aggregate the time series data. The alerts feature can be used to set up triggers or conditions that will transmit a notification through external sources such as email, Slack, etc. For example, an alert that the system has slowed down can be fixed by the user by allocating more server space to the system. The data in Prometheus can be displayed in tabular forms or graphs using the Prometheus web user interface. APIs can be used to integrate Prometheus with different types of display devices. 

When is Prometheus a good fit?

Prometheus is a great fit for any business looking for low-cost reliability in system monitoring. Prometheus offers excellent features and functionality to record numeric data series. It works great service-oriented architectures or machine-learning monitoring. One of the primary strengths of Prometheus is that it offers support for multi-dimensional data collection and queries. During outages, Prometheus is a reliable application to diagnose problems with the system. As Prometheus is a stand-alone system, its performance is not affected by network or remote service disruptions. 

When is Prometheus not a good fit?

Although Prometheus offers outstanding reliability even under failure conditions, the depth and accuracy of data provided by Prometheus are not ideal. Depending on the requirements of the users, the collected data by Prometheus might not be detailed enough.  Companies without an in-house monitoring service will require the system administrator to configure a job to retrieve metrics. This results in additional dependencies to keep a track of by the system administrator. Compared to some of the other software used for similar applications, such as Grafana or Nagios, Prometheus requires more maintenance efforts.