#pseudo code

use Parallel::ForkManager;

$threads = 20

my $pfm = new Parallel::ForkManager( $threads );

FOREACH: foreach my $thing(keys %{$things_hr}) {

    my $pid = $pfm->start and next;

#do stuff

    	push @names, $name;
#do stuff

	$thing{$name}{a} = $value1;
	$thing{$name}{b} = $value2;

#do stuff

	$list{$id}{$name}{b} = $b;
	$list{$id}{$name}{e} = $b1;
	$list{$id}{$name}{a} = 0;
	$list{$id}{$name}{c} = $ar->[$id][3];
	$list{$id}{$name}{i} = $ar->[$id][1];
	$list{$id}{$name}{j} = $ar->[$id][2];
	$list{$id}{$name}{k} = sprintf("%.4f",$ar->[$id][9]);


$pfm->finish;
  

$pfm->wait_all_children;