Keep in mind the date it was written -- this was before SSDs and in the days of tiny heaps. Any improvement upon seek times of what were then commodity disks (SCSI/SAS being insanely expensive and out of bradfitz' reach, afaik) would easily dominate the cost of Perl's runtime (which, in retrospect, isn't horribly bad -- the GC and VM are more mature and less trouble-prone than most common scripting languages, although nowhere near LuaJit or any modern Scheme/Common Lisp implementation).