[jetty-user] Jetty, JMeter and Keep-Alive

I have a old school, pre SOAP/Web Service buz, "REST/POX" service that
process requests in real time. I.e: It receives XML does something with it
and responds back to the client. In general average response time is
200-300ms

So I have couple thousand clients who connect to this service. Not to many
clients but each client is high volume, as in each client is capable of
making 100 000+ request per day. Over the course of the day average
requests per second are NOT so high, but there is peek times where it can
reach 200 requests a second.

Each request is 1 connection, request, 1 response, close connection.

Now I converted this old service to real REST using Jersey and Jetty and I
proceeded to performance test it. I setup JMeter...

10 threads - HTTP Request Sampler - Assertion Response - Summary report

And I got 2100 requests per second great!

Then I disabled Keep-Alive in Jmeter as clients don't really use it and as
described above this isn't a Keep-Alive type of application.

So now JMeter seems to hang or pause or freeze or what ever. So I though ok
maybe it's Jersey, but it's not it seems to happen even on just calling a
simple index.jsp which just prints Hello World!

1- I want to make sure it's not Jetty
2- Is Keep-Alive something I want to consider as clients connecting aren't
exactly capable of managing Keep-Alive connection provided their APIs do it
for them and if even.
3- Is there a way for me to test the 2000 requests second and make sure
Jetty truly does work correct without Keep-Alive
4- is it possible that JMeter without Keep-Alive is creating so many open
client connections that neither client machine or server machine can handle
so many open connection? (using Windows 2003 and JDKu27 on both client and
server machine)