This small webapp is intended to give you a rough feeling about JTA vs resource-local JPA transactions
Just deploy the WAR and browse the page. It contains a download link to an Apache JMeter (http://jmeter.apache.org) benchmark script.
$> mvn clean install tomee:run
Open the jtabench.jmx file in Apache JMeter and activate one of the two sites. Between the rounds invoke http://localhost:8080/jtabench/customer/reset to clean all customers from the DB again