Web app deployment in Tomcat

Question

Does Tomcat use a different Java Virtual Machine (JVM) for each web application running in its container, or does all web applications in Tomcat run under the same JVM?

So for a specific example: if a web application under webapps, enables JMX programmatically (via System properties) does this mean that JMX is enabled for all web applications running in the container?

I believe this is the case, but would like to confirm.

This question came up from my problem in this thread: question on tomcat and jmx . Any input on the subject is appreciated.

Answer 1

Tomcat runs in a single JVM, so every app deployed to a single tomcat instance runs in the same VM as every other application. They get different classloaders, so they're isolated from each other in that sense, but the JVM is the same.

So any feature enabled JVM-wide will be enabled for every application in that instance.