The measure is taking against 1000 runs of cloning a same object, and the class loading should not be a big impact here. By the way, the smartClone method provided works great. On my test, it is more than twice as fast as the standard serialization. ------------- ByteArrayOutputStream bstream = new ByteArrayOutputStream(); org.jboss.serial.io.JBossObjectOutputStream out = new org.jboss.serial.io.JBossObjectOutputStream(bstream); Object newobj = out.smartClone(obj); View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3985027#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...