use strict;
use threads;

open my $fh, '>', 'outfile' or die $!;
my $th = 0;
my @threads = map {
    $th++;
    async( sub { sleep(1); for(1 .. 30_000) { print $fh "Thread $th\n" } } );
} (1 .. 500);
$_->join foreach @threads;
close $fh;

##</code><code>##

Thread 3Thread 349
Threead 85
Thread Thread 333
Thre59
ad 349
Thread 3ad 333
Thread 3Thread 359
Thre49
33
ad 295
ThreThread 333
Thread 8Thread 338
ThreThread 350