use Parallel::ForkManager;

  $pm = new Parallel::ForkManager(100);
  my @all_data = qw/1/;
  foreach $data (@all_data) {
    # Forks and returns the pid for the child:
    my $pid = $pm->start; 
    print "PID $pid\n";
    $pid and next;
    print "$data", "\n";
    while(){}; # 100% CPU
    $pm->finish; # Terminates the child process
  }
 $pm->wait_all_children;