The global transaction timeout is controlled in the jboss-service.xml of JBOSS_HOME/server/conf which by default is 5 minutes (search for the
string 300 in that file). However, if you want to control it at individual component level, then it depends on the component(s) in that flow. But since you say, you want this to be applicable only when you are debugging, I guess the jboss-service.xml file is what you are looking for.