[OAK-2755] Consolidated JMX view of all EventListener related statistics

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.0.13, 1.2.2, 1.3.0, 1.4
• Component/s: core
• Labels: monitoring observation
• Assignee: Marcel Reutegger
• Reporter: Chetan Mehrotra
• Created: 12/Apr/15 14:45
• Updated: 26/Sep/19 11:40
• Resolved: 16/Apr/15 13:13

Description

Oak Observation support exposes a EventListenerMBean [1] which provide quite a bit of details around registered observation listeners. However in a typical application there would be multiple listeners registered. To simplify monitoring it would be helpful to have a consolidated view of all listeners related statistics.

Further the stats can also include some more details which are Oak specific

• Subtree paths to which the listener listens to - By default JCR Api allows single path however Oak allows a listener to register to multiple paths
• If listener is enabled to listen to cluster local and cluster external changes
• Size of queue in BackgroundObserver
• Distribution of change types present in the queue - Local, External etc

[1] https://github.com/apache/jackrabbit/blob/trunk/jackrabbit-api/src/main/java/org/apache/jackrabbit/api/jmx/EventListenerMBean.java

Issue Links

• is duplicated by: OAK-2676 Expose stats around BackgroundObserver queue
• is related to: SLING-5384 Expose BackgroundObserverMBean as part of OakResourceListener setup
• relates to: OAK-2596 more (jmx) instrumentation for observation queue