A lot of languages claim to have "no arbitrary size limits" for strings and files or that the limits to the sizes of their thingies is limited only by available memory or hard disk space.
What I have learned from Tilly's post is that we Perl advocates cannot make such a claim. Perl programs can break if confronted with a file size of greater than 2 GB. And since hard disks often come with much more space than that, and since the poster obviously has a need to work with such files, this deficiency is not a trivial one.
"Nothing is difficult for the man who doesn't have to do it himself." All hail the worthy work of the Perl Porters who got us where we are today (with a little help from ActiveState and thus B. Gates.) I intend no disparagement of their magnificent work.