Which critical performance metrics can be monitored by the Prometheus system?

Prometheus system can be used to monitor essential performance metrics such as CPU utilization, memory utilization, disk usage, network traffic, request response time, error rate, etc. Its flexible query language and powerful data storage capabilities allow users to customize monitoring metrics and perform real-time monitoring, alerting, and data analysis as needed. Additionally, Prometheus supports various data visualization tools like Grafana to help users visually understand the system performance status.