The interval (REREGISTER_DELAY) between apps re-registering themselves should be a setting

In dk.netarkivet.monitor.distribute.JMSMonitorRegistryClient
It is currently hardwired in the REREGISTER_DELAY constant that all applications re-register themselves every minute.

This ought to be configurable. In the case of a NetarchiveSuite installation with applications on many machines this will cause the jmsbroker to be flooded with messages.
Incidentally we have actually patched the local 3.6.0 installation to only reregister every 5 minutes.