Performance Monitoring Infrastructure (PMI) collects performance data for 4.0 and 5.0 Java Database Connectivity (JDBC) data sources. For a 4.0 data source, the data source name is used. For a 5.0 data source, the Java Naming and Directory Interface (JNDI) name is used.
The JDBC connection pool counters are used to monitor the performance of JDBC data sources. You can find the data by using the Tivoli performance viewer and looking under each application server by click application_server > JDBC connection pool.
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 | Granularity | Type | Level | Overhead |
| Num creates | connectionPoolModule.numCreates | The total number of connections created | Per connection pool | CountStatistic | All | Low |
| Pool size | connectionPoolModule.poolSize | The size of the connection pool | Per connection pool | BoundedRangeStatistic | All | High |
| Free pool size | connectionPoolModule.freePoolSize | The number of free connections in the pool (apply to 5.0 DataSource only) | Per connection pool | BoundedRangeStatistic | Basic | High |
| Num allocates | connectionPoolModule.numAllocates | The total number of connections allocated | Per connection pool | CountStatistic | All | Low |
| Num returns | connectionPoolModule.numReturns | The total number of connections returned | Per connection pool | CountStatistic | All | Low |
| Concurrent waiters | connectionPoolModule.concurrentWaiters | The number of threads that are currently waiting for a connection | Per connection pool | RangeStatistic | All | High |
| Faults | connectionPoolModule.faults | The total number of faults, such as timeouts, in the connection pool | Per connection pool | CountStatistic | All | Low |
| Num closes | connectionPoolModule.numDestroys | The total number of connections closed. | Per connection pool | CountStatistic | All | Low |
| Avg wait time (ms) | connectionPoolModule.avgWaitTime | The average waiting time in milliseconds until a connection is granted | Per connection pool | TimeStatistic | All | Medium |
| Avg use time (ms) | connectionPoolModule.avgUseTime | The average time a connection is used (apply to 5.0 DataSource only). Difference between the time at which the connection is allocated and returned. This value includes the JDBC operation time. | Per connection pool | TimeStatistic | All | Medium |
| Percent used | connectionPoolModule.percentUsed | The average percent of the pool that is in use | Per connection pool | RangeStatistic | Basic | High |
| Percent maxed | connectionPoolModule.percentMaxed | The average percent of the time that all connections are in use | Per connection pool | RangeStatistic | All | High |
| Prepared stmt cache discards | connectionPoolModule.prepStmtCacheDiscards | The total number of statements discarded by the least recently used (LRU) algorithm of the statement cache | Per connection pool | CountStatistic | All | Low |
| Num managed connections | connectionPoolModule.numManagedConnections | The number of ManagedConnection objects in use for a particular connection pool (applies to V5.0 DataSource objects only) | Per connection factory | CountStatistic | All | Low |
| Num connection handles | connectionPoolModule.numConnectionHandles | The number of Connection objects in use for a particular connection pool (apply to 5.0 DataSource only) | Per connection factory | CountStatistic | All | Low |
| JDBC time | connectionPoolModule.jdbcOperationTimer | The amount of time in milliseconds spent running in the JDBC driver which includes time spent in the JDBC driver, network, and database (apply to 5.0 DataSource only) | Per data source | TimeStatistic | All | Medium |