This is a follow-up on the "out of connections" error I am periodically 
receiving from the production MySQL DBMS.

If you will recall, where we left it was that the evidence appears to support 
the interim conclusion that it is not Cayenne and that it may be the JDBC 
Driver or even MySQL.

Actions Taken (based on previous input):
I upgraded the connector to "mysql-connector-java-5.1.12" and the MySQL server 
was reluctantly upgraded by the webhost tech-person to "MySQL/5.0.88"  (it 
appears they do not like MySQL 5.1 for some reason).  I also perused my code 
for any "open" connections (which I am not sure that I have any control over 
since all DBMS connections are managed by Cayenne).

Results:
It appears that the problem continues.  It even occurs with *very* light usage. 
There does not seem to be any obvious trigger. This causes sever symptoms of a 
request for a webpage taking 30-60 sec to load.  (It appears that the 10 
used-connections somehow magically allow the user to access after this 30-60 
sec delay.  ????????????)

Question:
I am pretty good at tracking down bugs, but this one is really difficult to 
devise a methodical plan to solve.  My only idea right now is to monitor the 
Cayenne managed connection pool (with the hopes that I can monitor open 
connections and associate these connections with the cause).  I have not been 
able to figure out how to do this via the Cayenne API.  I am convinced that 
monitoring this connection pool will provide insight into a problem.

Therefore: can you provide some example code of how to monitor open (and 
closed) connections in the Cayenne managed connection pool (so that I can 
display the result in a JSP)?

Thanks,
Joe


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