The good news is that Glassfish is now working very well. The bad news is I don't know exactly what fixed it. Here's the scenario that fixed it though:
* Inherited Glassfish install from previous developers.
* Found out that they had always done upgrades by copying the domain folder to a new Glassfish install.
* Created a new domain and reinstalled all war, jar, and ear files.
* Now it doesn't lock up any more and performs much better. What were the offending configuration items? I can't tell. But at least it's working.
My faith in Glassfish is much restored because we did some load testing and it easily handled what we threw at it.
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