Once the libraries are properly installed and available to Java (if loading fails, the library path will be displayed), the Tomcat connectors will automatically use APR. Configuration of the connectors is similar to the regular connectors, but have a few extra attributes which are used to configure APR components. Note that the defaults should be well tuned for most use cases, and additional tweaking shouldn’t be required.
When APR is enabled, the following features are also enabled in Tomcat:
- Secure session ID generation by default on all platforms (platforms other than Linux required random number generation using a configured entropy)
- OS level statistics on memory usage and CPU usage by the Tomcat process are displayed by the status servlet
