Query Monitoring

Use the Query Monitor to measure query executions and cache hits. This can be useful for performance analysis in a complex system.

Enable the Query Monitor in either of these ways:

• Set the System property org.eclipse.persistence.querymonitor=true.

• In persistence.xml, set <property name="eclipselink.profiler" value="QueryMonitor"/>

The monitor dumps the number of query cache hits and executions (misses) once every 100 seconds.

For more information about querying, see Chapter 10, "Understanding Queries."