foreach my $ln (@lines) {
  $pm->start && next;
    ** child starts
     my $dbh = $this->_child_db();
   ... code here
    ** child finishes with _close_child();
    $this->_close_child();
  $pm->finish
}


$pm->wait_all_children()


_child_db() {
  if (!$this->{'_dbh-child')) {
    print $$ . ": Creating Child DB Handle";
    $this->{'_dbh-child'} = new DBI::Connect ......;
  }
  return $this->{'_dbh-child'};
}

_close_child() {
  print $$ . ": Closing child DB Handle";
  $this->{'_dbh-child'}->disconnect();
  delete($this->{'_dbh-child'});
}
[download]

Very rough, please don't try to compile it. All my code is on an internal system not connected to the internet.

Also -- I've added close and finish methods for each child process through ForkManager, too:

$pm->run_on_start(\&_child_start);
$pm->run_on_finish(\&_child_finish);

sub _child_start() {
 my ($pid, $ident) = @_;
 print "**** STARTED: child with PID $pid";
}

sub _child_finish(){
  my ($pid, $exit, $ident) = @_;
  print "**** FINISHED: child with PID $pid exit cide $exit";
}
[download]

-- philip
We put the 'K' in kwality!