isPaging is used only on TransactionImpl. And we are not actually page if isPaging. We are just holding the message until commit is called, when we will actually call addSize and route the message again. This is because I can't page a message for a pending transaction. We don't have control when the commit will come (it could be waiting an user action). Later when commit is called, addSize is used, and the message will only go towards paging, if is in page mode. When we have the HugeTransactionSupport in place, that will be done in another thread. So, when the HugeTransaction is in place, when isPaging = true, we will delay the messages on another file, when commit is called we will transfer the temporary repository towards routing what could lead to paging. On the non-transactional use-case, we aways use addSize. Unless something was recently changed. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4197888#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...