This week's book giveaway is in the Mac OS forum. We're giving away four copies of a choice of "Take Control of Upgrading to Yosemite" or "Take Control of Automating Your Mac" and have Joe Kissell on-line! See this thread for details.
I read that the container creates for each request captured a thread. I know that one thread is generated to handle one Servlet instance, if you have ten started Servlets and all up, so you got one thread for each Servlet started, but for each request do you have addicional threads running?
To answer your questions, if servlet implements Single Thread Model then vendor can implement STM by creating multiple instances of servlet and make sure that every sevlet instance creates only one thread at a time.