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0 Years ago, i believe Q4-2000, we made a website that almost from the day it went live had to serve some rather heavy content with 30.000 hits a day. We finally settled on a cluster of 3 Tomcat-4 servers, 2 MySQL DBs, some homebrewed caching (site was read-mostly), some light TX-management and straight JDBC with (cached) prepared statements. That’s it. Surprisingly, the performance was great!
Nowadays EJBs would probably be used for this, but i’m still not convinced why.
I have the feeling that there is indeed some threshold in the level of importance of a managed environment/container for a project, above which the use of EJBs over other frameworks is justified, but i believe the threshold is much higher than should be expected from the percentage of applications using them.
Any thoughts on this?
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Some very useful thoughts on this issue may be found in Rod Johnson’s book “Expert one-on-one J2EE design and development”, Chapter 6 and 7.