Prometheus Has a Free Monitoring System With a Powerful Query Language

Prometheus is the CNCF graduated monitoring system. It collects metrics via pull model, stores them in a time-series database, and provides PromQL for powerful queries. What You Get for Free Pull-based collection — scrapes targets automatically PromQL — powerful query language Alertmanager — routing, silencing, grouping Service discovery — Kubernetes, Consul, DNS, file Client libraries — Go, Java, Python, Ruby, .NET Federation — hierarchical metric collection Recording rules — pre-compute expensive queries Quick Start docker run -p 9090:9090 prom/prometheus prometheus.yml scrape_configs : - job_name : ' my-app' static_configs : - targets : [ ' localhost:8080' ] scrape_interval : 15s PromQL Examples # Request rate rate(http_requests_total[5m]) # Error percentage sum(rate(http_requests_total{status=~"5.."}[5m])) / sum(rate(http_requests_total[5m])) * 100 # Top 5 memory consumers topk(5, container_memory_usage_bytes) Prometheus vs Datadog Feature Prometheus Datadog Price Free (OSS) $15/ho