We use an application made by HPE which blocks completely from time to time. The application comes with Java 6, uses ojdbc6 and connects to Oracle 11. HPE claims that when one of our 6 application servers dies when it runs a blocking update to a central table this causes the Oracle server to wait infinitely effectively rendering all servers defunct. I can see the blocking statement (our DBA showed me) and can see that the connection pool of all servers grows until it hits a defined maximum. But I have doubts that Oracle does not detect the died connection.
Can someone confirm HPEs theory or give me a hint to further diagnose this ?