To notify on-call engineers about service degradation quickly, what is the best approach?

Utilizing Stackdriver Monitoring to monitor resources and raise alerts is an effective approach for notifying on-call engineers about service degradation promptly. This tool is specifically designed to provide insights into the performance and availability of your applications and services within Google Cloud.

Stackdriver Monitoring allows you to set up custom alerting policies based on specific metrics, such as CPU utilization, memory usage, or any other relevant performance indicators. When these metrics exceed predefined thresholds, the system can quickly trigger notifications through various channels, such as email, SMS, or other incident management systems. This ensures that on-call engineers are alerted in real-time, enabling them to respond to issues quickly and mitigate potential downtime or service impact.

In contrast, while Cloud Functions can automate certain tasks and Cloud Pub/Sub can facilitate messaging between applications, they are not primarily focused on monitoring and alerting. Stackdriver Error Reporting captures and aggregates application errors, which is useful for debugging but not specifically tailored for monitoring service performance. Therefore, Stackdriver Monitoring remains the most direct and efficient way to ensure that on-call engineers receive timely notifications regarding service degradation.