I have a Java application running in WebLogic 11g on Windows, which after several days, becomes unresponsive. One suspicious symptom I've noticed is that a large number of connections (about 3000) show up in netstat with a CLOSE_WAIT status even when the server is idle. Since the application server is managing the client connections, I'm not sure what's causing this. We also make a number of web service calls that loopback to the same server, but I believe those connections get closed properly. What else could cause this and how does one troubleshoot a problem like this?
The problem was a bug triggered by setting "Use JSSE SSL" to true in webLogic. Using WebLogic's own SSL implementation instead of JSSE is not a problem for our application, so I merely unchecked that setting and the problem disappeared.