activemq shutdownHook

[heatlamp]

Using Fuse 4.4 and Kahadb, I'm confused about the need for/exact function of the ActiveMQ 'shutdownHook': http://activemq.apache.org/broker-uri.html.  

I assume this has something to do with container ActiveMQ lifecycle, but in what circumstances should this be set set true?

Thanks, Jim

[garytully]

When useShutdownHook=true, the broker registers a shutdown hook with the jvm

 Runtime.getRuntime().addShutdownHook

from which it calls broker.stop(). If the jvm is shutdown before the broker is stopped, then it will do a clean shutdown as part of the jvm callback. It is always better to do a clean stop of the broker because it will ensure a speedy restart as all in-memory data will have been checkpointed.

If an application or container wants to manage broker shutdown via a shutdown hook, such that it can control the shutdown order of components, it should disable the broker hook, which defaults to true.

[heatlamp]

Thanks, Jim