Which service provides insights into operational health and responds to performance changes?

Amazon CloudWatch is the service that offers detailed insights into operational health and allows users to respond to performance changes effectively. It does so by providing a comprehensive monitoring solution that tracks resource utilization, application performance, and operational health in real-time. CloudWatch collects and visualizes metrics and log files, setting alarms on various thresholds to notify users when performance deviates from the expected behavior. This proactive monitoring capability enables quick reactions to performance issues, safeguards against downtime, and helps optimize operational efficiency.

In contrast, while AWS Systems Manager provides operational data and aids in resource management and automation tasks, its primary focus is not solely on monitoring performance changes. AWS Config focuses on compliance by tracking configuration changes over time, ensuring that resources remain secure and compliant with organizational policies rather than monitoring operational performance. AWS Trusted Advisor offers best practice recommendations for optimizing AWS accounts, but it does not actively monitor performance metrics or provide real-time insights into operational health. Thus, Amazon CloudWatch stands out as the primary service designed specifically for monitoring and responding to changes in operational performance.