The Java 2 Connector (J2C) connection pool counters are used to monitor J2C connection pool performance.
Note: With the instrumentation level set to anything other than MAX, the values may be less accurate for TimeStatistics and CountStatistics (and in the case of CountStatistics, such as numConnectionHandles, can even be negative). This is due to counters not being synchronized. Synchronizing counters is very expensive in terms of resources, so it is only done when the instrumentation level is set to MAX.
Name | Key | Description | Version | Granularity | Type | Level |
Num Managed Connections | j2cModule.numManagedConnections | The number of ManagedConnection objects in use | 5.0 | Per connection factory | CountStatistic | Low |
Num Connection Handles | j2cModule.numConnectionHandles | The number of connections that are associated with ManagedConnections (physical connections) objects in this pool | 5.0 | Per connection factory | CountStatistic | Low |
Num Connections Created | j2cModule.numManagedConnectionsCreated | The total number of managed connections created | 5.0 | Per connection factory | CountStatistic | Low |
Num Connections Destroyed | j2cModule.numManagedConnectionsDestroyed | The total number of managed connections destroyed | 5.0 | Per connection factory | CountStatistic | Low |
Num Connections Allocated | j2cModule.numManagedConnectionsAllocated | The total number of times that a managed connection is allocated to a client (the total is maintained across the pool, not per connection). | 5.0 | Per connection factory | CountStatistic | Low |
Num Connections Freed | j2cModule.numManagedConnectionsReleased | The total number of times that a managed connection is released back to the pool (the total is maintained across the pool, not per connection). | 5.0 | Per connection factory | CountStatistic | Low |
Num Faults | j2cModule.faults | The number of faults, such as timeouts, in the connection pool | 5.0 | Per connection factory | CountStatistic | Low |
Free Pool Size | j2cModule.freePoolSize | The number of free connections in the pool | 5.0 | Per connection factory | BoundedRangeStatistic | High |
Pool Size | j2cModule.poolSize | Average number of managed connections in the pool. | 5.0 | Per connection factory | BoundedRangeStatistic | High |
Concurrent Waiters | j2cModule.concurrentWaiters | Average number of threads concurrently waiting for a connection | 5.0 | Per connection factory | RangeStatistic | High |
Percent Used | j2cModule.percentUsed | Average percent of the pool that is in use | 5.0 | Per connection factory | RangeStatistic | High |
Percent Maxed | j2cModule.percentMaxed | Average percent of the time that all connections are in use | 5.0 | Per connection factory | RangeStatistic | High |
Avg Wait Time | j2cModule.avgWait | Average waiting time in milliseconds until a connection is granted | 5.0 | Per connection factory | TimeStatistic | Medium |
Avg Use Time | j2cModule.useTime | Average time in milliseconds that connections are in use | 5.0 | Per connection factory | TimeStatistic | Medium |