13.6.2. Hot Deployment Build Details

JBoss AS, JBoss EAP, Tomcat 6, and Tomcat 7
When JBoss AS, JBoss EAP, Tomcat 6, and Tomcat 7 applications are hot deployed, the Maven build is executed (either with Jenkins or without), but the server does not restart. Following the build, the JBoss HDScanner notices any modifications and redeploys them. If previously deployed artifacts are removed as part of the update, they are undeployed automatically.
PHP, Zend Server, Perl, Python, and Node.js
When PHP, Zend Server, Perl, Python, and Node.js applications are hot deployed, the application code is built (dependencies are processed and user build action_hooks are run) and deployed to the application server. The server does not restart. This is true regardless of whether an application has Jenkins enabled or not. For applications that have Jenkins enabled, the build is performed on a Jenkins slave instance and then synced to the gear(s) where the application server is running.
Ruby
When a Ruby application is hot deployed, the Passenger restart.txt file is touched, and the application server serves the new code without requiring a full server restart. See the Passenger Documentation for more information.