A couple more ideas (sparked by the 80,000) :

1. Try binding the return values. e.g.

   my $imei;
   $rc = $sth_imei->bind_col(0,\$imei);
   $sth_imei->execute();
   $sth_imei->fetch();
   print "IMEI : $imei\n";
   [download]

2. If you don't want to do that, at least use ->fetchrow_arrayref(). Otherwise, each execute call has to create a new list for you. The _arrayref gives you a ref. to a static array, so less copying.
3. bind_param should take a colum number shouldn't it, not a name, e.g. $sth_imei->bind_param(0,$rec[1])

Either of the first 2 should save time, given 80,000 iterations.
Finally, note that execute() can return '0E0' meaning 0 but true, meaning no rows (and different to undef for errors). May be worth checking for that explicitly.
I think I'm out of ideas now...
--
Brovnik