What is the role of metrics in monitoring and evaluating application performance?

Metrics in application monitoring are quantitative indicators that reflect the state and performance of the system. They help understand how the application works, identify issues, and make decisions for optimization. For example, metrics can include response time, number of requests per second, memory and CPU usage, and error count.

Using metrics, you can:

• Monitor the stability and performance of the application in real-time.
• Quickly identify anomalies and failures.
• Analyze trends and plan scaling.
• Evaluate the effectiveness of changes and new releases.

In Go, libraries like Prometheus client are often used to collect metrics and integrate them into the monitoring system.