Monitoring

The driver uses JMX to create MXBeans that allow an application or end user to monitor various aspects of the driver.

The driver creates MXBean instances of a single type: ConnectionPoolStatisticsMBean. The driver registers one ConnectionPoolStatisticsMBean instance per each server it connects to. For example, in the case of a replica set, the driver creates an instance per each non-hidden member of the replica set.

Each MXBean instance is required to be registered with a unique object name, which consists of a domain and a set of named properties. All MXBean instances created by the driver are under the domain "org.mongodb.driver". Instances of ConnectionPoolStatisticsMBean will have the following properties:

• clusterId: a client-generated unique identifier, required to ensure object name uniqueness in situations where an application has multiple MongoClient instances connected to the same MongoDB server deployment
• host: the host name of the server
• port: the port on which the server is listening
• minSize: the minimum allowed size of the pool, including idle and in-use members
• maxSize: the maximum allowed size of the pool, including idle and in-use members
• size: the current size of the pool, including idle and and in-use members
• waitQueueSize: the current size of the wait queue for a connection from this pool
• checkedOutCount: the current count of connections that are currently in use