Are typically caused by growing amount of loaded Class objects. It may be caused by:
- own Java code using third party library which is loaded/unloaded every time graph is executed
- non-bundled JDBC/JMS/* driver usage (*.jar selected in Connection wizard) - this driver is loaded/unloaded every time graph is executed
This problems are typically related to driver/library which is not written in a way that expects dynamic loading/unloading. Solution is to place this driver/library into Server classpath and refer it by class name and not via driver location.
Typically caused by something cached (connections, values in hash, ...) in static way.