If you're running this script in Windows you can use the Win32::GetTickCount to get the time in miliseconds
I would do something like this:
in reply to RE: RE: How can I keep track of the execution time of a script?
in thread How can I keep track of the execution time of a script?
$ms = Win32::GetTickCount();
warn 'This script took ',Win32::GetTickCount() - $ms,'miliseconds';