Start one more mongrel for development

I started a mongrel, open a test page, then started a loop action from
the page. The action would take a loooooong time to finish. Not wanting
to waste my time on waiting, I started another mongrel at another
port(3001), wished to do other jobs. But to my surprise, this new
mongrel joined the first one, and went on with the same loop action! Is
it ok for the loop action? I mean these mongrels are cooperating, so the
loop will be finished faster, but no just repeat the loop twice, right?
and can I open another test page on and do other
jobs now?

and what about starting a third mongrel?