Finding and Reporting Connection Leaks Web Application.

Question

So we have a web application that we know has connection leak(s). I have developed a test plan with JMeter to load test the app, but how do I find and report the connection leak, and what is the best tool to use for that? Basically my test plan runs through a use case scenario. I have added different types of listeners using jmeter to report different types of information that I get back.
Also, is there a way to get the report back as a jsp, html page? Something kind of like the JUnit test reports do
I would like the jmeter test to run, give the url, name of task-maybe, the time it took, success or fail, and current status - connected?
Thanks in advance.
orozcom

Answer 1

What connections are those - sockets, database, ...? Actually, that doesn't probably matter. I'd use "grep" to find leaks of any kind. Every critical resource should be handled with try/finally:
    foo()
        WhateverConnection connection = null;
        try {
            connection = ConnectionFactory.openConnection();
            ...use it...;
        } finally {
            ConnectionFactory.close(connection); // Static function so that works with null
    }That goes for files, db connections, sockets, everything.
Then any use of openConnection() that doesn't match that pattern is wrong and must be fixed. "grep" plus visual inspection should do it. They may be other pieces of code that are technically correct but look different; those are to be considered bugs and must be modified to conform to the exact same code template. All connection openings must look the same; the code audit easily misses bugs if each developer comes up with his own clever pattern.
Finding leaks by testing will never find them all. Especially leaks that occur due to exceptions. try/finally is the right way to deal with those.
Additionally, the connection factory could keep a list of open connections, and list them at request. I also like to log statistics periodically from the connection pool: how many connections have been opened, how many are open, how long min/max/average time a connection gets used, how much data are transferred, etc.