Google Kubernetes Engine (GKE) is a managed containerized application service on Google Cloud Platform, allowing cluster operators to focus on running applications without managing the Kubernetes control plane. GKE comes in two modes: Standard and Autopilot, with the latter providing automated node management. To effectively monitor GKE clusters, it's essential to collect metrics and performance data from across the cluster, including CPU and memory usage, container and pod events, network throughput, and individual request traces. Datadog is a key tool for monitoring GKE, providing components such as the Datadog Agent and Cluster Agent that can be deployed to monitor the cluster. The Datadog Agent collects metrics and logs from pods in the cluster, while the Cluster Agent acts as a proxy for node-based Agents and provides additional features like Kubernetes Admission Controller. To deploy the Datadog Agent and Cluster Agent, prerequisites include enabling the Datadog GCP integration and collecting GKE control plane metrics. Once deployed, the Datadog Agent provides access to various dashboards and visualizations, including the GKE Standard and Enhanced dashboards, as well as the Kubernetes Overview Page and pods view. These tools offer features like Watchdog Insights and flame graphs to help troubleshoot issues in the cluster. Additionally, Datadog provides application-level metrics through its APM feature, allowing users to correlate performance data across infrastructure components and gain deeper insights into their system's health and performance.