What people are tellng you about split, etc. is good. I would guess that the dog in your routine is the $lsl = `ls -l "$fnm" 2>&11`; line. Invoking a process is expensive, going to the filesystem is also expensive.

... Got called away for a few hours ...

This is a design issue most likely. Instead of passing one filename to ls repeatedly it is better to collect your filenames and make one run of ls. Then mangle all that data to your hearts content.