$| = 1;
my @data;
$#data = 8500000;
$#data = -1;
while(<>) { push @data, $_ }

print "sorting...\n";

use Sort::Key qw(ukeysort_inplace);
ukeysort_inplace { (split(/\t/))[2] } @data;

print "sorted\n";
sleep 100;