A little more information would go a very long way to allowing us to do something other than guess.
Which version of Perl? Which OS? What does the script do? Does it use threads? Spawn processes? Use external resources like DB's, IPC etc?
Examine what is said, not who speaks.
1) When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.
2) The only way of discovering the limits of the possible is to venture a little way past them into the impossible
3) Any sufficiently advanced technology is indistinguishable from magic.
Arthur C. Clarke.