"Prometheus is an open source monitoring system and time series database. Prometheus includes a multi-dimensional data model, a query language called PromQL, and a pull model for gathering metrics from your different services. Prometheus is widely used by large distributed systems deployments such as Kubernetes and Cloud Foundry.
Visit prometheus.io for the full documentation, examples and guides.
Prometheus (software) - Wikipedia
Prometheus, a Cloud Native Computing Foundation project, is a systems and service monitoring system. It collects metrics from configured targets at given intervals, evaluates rule expressions, displays the results, and can trigger alerts if some condition is observed to be true."
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"Open source, horizontally scalable, multi-tenant Prometheus as a service"
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Both in GoLang :)