Testing server response time is not something you should put much time in hand-rolling yourself. There are a number of utilities that do this, not all in perl. I've had decent success with Apache JMeter, but that doesn't mean you shouldn't research other tools.
in reply to Performance testing using Parallel::ForkManager?
I'm not here to plug jmeter, but it's worked great for me in monitoring response time under load.
I'd be very curious if other monks have successfully handled this type of issue purely with perl, since I've always wanted to but never *needed* to (due to the presence of existing utilities.)