JBOSS App Server vs. Glassfish
Solution 1:
We have studied relative performance of JBoss vs. Glassfish, and found that Glassfish scales much better under high loads.
Solution 2:
you may want to try your questions over at stackoverflow.com. At my company the programming teams set up those application servers and then work with production support. We keep JBoss in our repository because of all the configuration changes and each server we deploy needs to be slightly modified.
I've enjoyed playing with JBoss and the people in the forums are pretty active, but I haven't worked with Glassfish so I can't give any comparisons, but a search returned :
https://stackoverflow.com/search?q=glassfish+jboss
Because I'm a new user I can't post all three links that I wanted to from that search, but there are several good answers from the search above.