Hi there, Trying my luck with JBossCache 1.4.1.SP1 on a Websphere 6.1.0.3 cluster with 2 nodes each node with 1 server. The OS on both machines is Windows XP Professional SP2. I'm using the replSync-service.xml configuration file supplied in download ( etc\META-INF folder ). I've changed only the cache mode to INVALIDATION_SYNC because I need the sync happen sync and REPL_SYNC was too slow. I'm running some tests which do both cache read / write I'm getting lots of org.jboss.cache.lock.TimeoutException when acquiring locks. The scenario in which the TimeOut occurs is the following : All the operations occur on a TreeCache with one node with one entry only in the node: in Node1 modify a node - the invalidation msg is snd in Node2 the WL is acquired by a user thread - the invalidation msg is rcv - the JGroups thread tries to put a WL and fails with a time out which is send to Node1 ..... and this keeps going on. What are the recomandations in this situations ( indeed this is an extrem situations with some many updates on the same entry ): 1. increase the timeout period ( the current one is zero ) 2. use optimistic locking ( how can I configure it ?) 3. other ? Thanks Ionut RUSU View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4017565#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...