That is highly dependent on your JVM; see
the Volano report for some comparative figures, esp. the network scalability figure (which is largely governed by threading behaviour). A highly tuned server JVM like JRockit might help you.
Are you implying that you have one servlet which starts up 75 threads? Or are you hitting the servlet engine with 75 simultaneous requests? They are two different things. In the former case, I would wonder whether this is really necessary and/or productive. In the latter case, I would ask what exactly you are doing in your servlet.
- Peter