It will optimize it if you use this syntax instead: ($y) = split(/\s+/,$x); As it says in the manual (perldoc -f split): ($login, $passwd, $remainder) = split(/:/, $_, 3); When assigning to a list, if LIMIT is omitted, Perl supplies a LIMIT one larger than the number of variables in the list, to avoid unnecessary work. For the list above LIMIT would have been 4 by default. In time critical applications it behooves you not to split into more fields than you really need. -AM