I'm looking for a bit of understanding on just how Undertow handles large numbers of requests coming into a server.  Specifically when more requests are being sent in than are being completed.  I've been doing some load testing on a CFML app (Lucee Server) where I happen to have my io-threads set to 4 and my worker-threads set to 150.  I'm using a monitoring tool (FusionReactor) that shows me the number of currently executing threads at my app and under heavy load I see exact 150 running HTTP threads in my app server, which makes sense since I have 150 worker threads.  I'm assuming here that I can't simultaneously process more requests than I have worker threads (please correct if I'm off there)  

So assuming I'm thinking that through correctly, what happens to additional requests that are coming into the server at that point?  I assume they are being queued somewhere, but

I've done a bit of Googling and reviewed some docs but haven't quite found any definitive information on this, and a lot of info I found was about Wildfly specifically so I wasn't sure how much of it applied.