Resources-consuming handler ?

I would like to know if the handler below consumes a lot of cpu-resources.

What the script does:
-receives a very long list of items (generally images, like tif, jpg, png) up to 500
-it calculates the amount of items/mb to fill a CD/DVD if near to the total capacity of a CD/DVD
-creates a new list and a new burn-folder for files exceeding the capacity of a CD/DVD

Tell me your meaning, thanks.

--some initial values to get started
set burn_f to ((path to pictures folder as text) & "Backup:" as text)
set vmdd to "CD"
set nm_cat to "Test"
-->set myfile to list of files

my import_files(myfile, nm_cat, vmdd, burn_f)
on import_files(myfile, nm_cat, vmdd, burn_f)
	--create multiple burn-folders if needed
	set burn_trg to nm_cat & "-" & vmdd & " 1" & ".fpbf"
	set flnr to 1
	set Cap_mb to 0
	local myfile
	local flnr
	local burn_trg
	if vmdd is "DVD" then
		set {minsz, maxsz} to {4670, 4690}
		set {minsz, maxsz} to {670, 690}
	end if
	--get burn-folder
	set burn_trg to alias (nm_cat & "-" & vmdd & " " & flnr & ".fpbf" as text)
	tell application "Finder"
		--sort items in groups
		set dd to 0
		repeat with i in myfile
			set dd to dd + 1
			set fsz to (size of i) / 1024 / 1024 as integer
			if fsz = 0 then
				set fsz to (size of i) / 1024 as integer
			end if
			--sum results
			set Cap_mb to Cap_mb + fsz
			if Cap_mb ≥ minsz and Cap_mb < maxsz then
				make new alias file of alias burn_trg to i
				--generate the next burn folder list
				copy items dd thru -1 of myfile to myfile
				set flnr to flnr + 1
				--create a new burn folder
				set new_fnm to (nm_cat & "-" & vmdd & " " & flnr & ".fpbf" as text)
				set burn_trg to (burn_f & new_fnm as text)
				make new folder at burn_f with properties {name:new_fnm}
				--reset mb counter
				set Cap_mb to 0
				make new alias file of alias burn_trg to i
			end if
		end repeat
		--burn folders now
		reveal alias burn_f
	end tell
end import_files