Under IIS, every time you access a .pl page, a new perl.exe process is created. They shouldn't hang around for long though - looks like you might have a script there which is not being friendly to your CPU!
I would suggest looking at PerlIIS (which ships with ActivePerl) - this will load perl into the web server via ISAPI, so it doesn't need to load a new perl.exe for every script hit. By default, it adds the mapping .plx for PerlIIS scripts. You can copy those settings to .pl to make the switchover seamless.
mod_perl under Apache doesn't have this problem.
Simon Flack ($code or die)
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