Hang Manager is an Oracle Real Application Clusters (Oracle RAC) environment feature that autonomously resolves hangs and keeps the resources available.
Enabled by default, Hang Manager:
Reliably detects database hangs and deadlocks
Autonomously resolves database hangs and deadlocks
Supports Oracle Database QoS Performance Classes, Ranks, and Policies to maintain SLAs
Logs all detections and resolutions
Provides SQL interface to configure sensitivity (Normal/High) and trace file sizes
A database hangs when a session blocks a chain of one or more sessions. The blocking session holds a resource such as a lock or latch that prevents the blocked sessions from progressing. The chain of sessions has a root or a final blocker session, which blocks all the other sessions in the chain. Hang Manager resolves these issues autonomously by detecting and resolving the hangs.