Hi, I haven't used Thread::Barrier myself, but from its description (on CPAN) it is not the right module for your usage here. It's for letting a bunch of threads start doing their things when some resource is ready, and to wait for each other to complete before advancing to the next workpice coming in.

You will need to read up on threads in general. You will probably not need anything more esoteric than threads. You might also look at fork, if parallellism is the point, and not threads per se.