It seems no body care about my problem :( Anyway, I'm still doing the test and finally find that whenever I write the following code in my run() method of the reader Thread, the reader has a big chance to get null from a specific node which should have value, the code is: @Override | public void run() { | while(true) { | try { | Thread.sleep(1000); | } catch (InterruptedException e) { | // TODO Auto-generated catch block | e.printStackTrace(); | } | int max = w.getKey(); | Node<String, TestBean> regionNode = cache.getNode(Fqn.fromString(region)); // just a test to check the root node of my test | max = regionNode.getChildren().size(); | logger.info("currently node (/testRegion) has " + max + " subnodes"); | int readPoint = Math.abs(RANDOM.nextInt() % (max == 0 ? 1 : max)); | if (readPoint == 0) { | readPoint = 1; | } | testRegion = Fqn.fromString(region + "/" + readPoint); | TestBean value = cache.get(testRegion, "DATA"); | logger.info("Get value ++++++++++++++ '" + value + "' in node '" + testRegion.toString() + "'."); | logger.info("/n/n/n"); | } | } Please pay attention to the red color, it seems has a significant impact to the passivation Thread, when it was uncommented, my reader thread will get nothing. When this part of code (the red part) was removed, everything is OK. Can anybody give me some clues about it, any response will be appreciated. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4198620#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...