Why is there a need for some 'threading' mechanism in Perl whereas it already has the 'fork' call? It appears to me
that around 90% of all that threads (such as in Java) are
useful for could be accomplished with the native fork() call
in Perl. Also, by playing with SIG triggers/set_priority call you may be able to do without a separate threading module/mechanism.
On the other hand, though, I think it's good to have alternative approaches. Say, I'm not even sure if fork() would work well on Windows (I don't do much Perl for that system), since under Unix fork() does a 'system call' to create a child process.