This document discusses various tools and techniques for diagnosing slow Hadoop jobs, including metrics and monitoring, logging and correlation, and tracing and analysis. It describes how to use Ambari metrics and Grafana dashboards to monitor cluster health and performance. It also explains how to leverage Hadoop audit logs and caller context to correlate job activity. Techniques for application tracing using YARN timeline service and tools like Zeppelin and Tez analyzer are presented to enable deep performance analysis of Hadoop jobs.