parse a file and collect data into H
pass its reference to Sub

sub Sub {
    
    my $Href = @_;
    my $n_processes = 16;
    my $pm = new Parallel::ForkManager($n_processes); 

    foreach my $key (keys %{$Href}) {
        
        my $var = $key->attribute;
        my $cmd = "SomeBinary ".$var;
        $pm->start and next; # do the fork
        system($cmd);
        $pm->finish;
    }
    pm->wait_for_all_children;
}