We've recently updated a number of our servers from JDK build 1.6.0_07-b06 to build 1.6.0_18-b07 as part of a series of security updates. Since the updates we've seen two jvm crashes, one of which seems to be covered by Sun as http://forums.sun.com/thread.jspa?threadID=5424728 , the other error produced a few Google hits but nothing formal on the Sun site. I've had a search around and couldn't find anything that recommended a particular version of the JDK as being more stable/reliable then another, though I did find quite a few people warning off build 18 in particular. Does anyone have any experience / recommendations are to a particular stable version of the JDK in a high thread count and high I/O environment. We're trying to decide wether to push forward to version 20 or to take the security risks and go back to version 07. Any recommendations , anecdotes, etc. gratefully received.