"jason.greene(a)jboss.com" wrote : They could retrieve an object, wait for some period time (during which the data has been gravitated to another node), then trigger an update which would fail. You describe a somewhat broken usage. Let me preface this by saying buddy replication is an advanced feature, not for the faint of heart, because it requires a lot of engineering effort on the part the writer of the app to ensure that the data is truly owned by one and only one node in the cluster. It would be great if that weren't the case, but the cost of not having it be the case is terrible performance due to constant gravitation calls. So, getting an object from the cache, holding a ref to it, allowing a concurrent request to go to another node that gravitates the cache tree, and then using the original object without re-fetching it from the cache -- that means the app is not properly ensuring ownership of the data. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4056720#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...