Monitoring helps you keep track of your Spring Boot application's health and performance. By collecting and analyzing metrics, you can quickly spot problems, understand how your application is used, and make informed decisions for improvements. In this chapter, you will learn what monitoring is, why it matters, and how it fits into your application's lifecycle.

Monitoring

Monitoring means observing your application’s behavior and performance in real time. In Spring Boot applications, monitoring helps you see how your app is running, spot problems early, and make sure everything works as expected.

Monitoring is important because it helps you:

• Detect issues before they affect users;
• Understand how your application uses resources, such as memory or CPU;
• Track how your app responds to different workloads;
• Respond quickly to errors and outages.

A key part of monitoring is collecting metrics. Metrics are numerical values that show how your application is performing. Common metrics include response time, memory usage, and the number of active users. These numbers help you understand what is happening inside your app.

Health checks are tests that show whether your application and its components are working properly. For example, a health check might confirm that your database connection is active or that your app can access a required service. If a health check fails, it usually means something needs attention.

Alerts notify you when something goes wrong. They are automatic messages sent when metrics or health checks show a problem, such as high error rates or slow response times. Alerts help you react quickly and keep your app running smoothly.

By using monitoring, you gain better control over your Spring Boot application, making it easier to maintain, troubleshoot, and improve over time.