You're welcome :-)

Not sure if you've noticed, but the solution I provided is capable of having the number of threads dialled up and down very easily. In fact, with very minor modifications, you can even create a non-threaded script (be sure to remove use threads and use Thread::Queue when you do this). I strongly suggest that you do this for testing (make sure to run your full workload, rather than just a print statement) - It will let you know if threading is actually helpful for your workload and if so let you dial in the optimal number of threads pretty rapidly.