# HTTP::Async
# this one will do 20mbps, fastest invokation for me was 
# perl -w httpasync.pl 0 15
use strict;
use warnings;
use threads;
use threads::shared;
use HTTP::Async;
use HTTP::Request;
use HTTP::Response;

my @urls : shared = <DATA>;
my $numchildren = $ARGV[0];
my $numthreads = $ARGV[1];
print "num children: $numchildren, threads: $numthreads\n";
my $pid = 0;
for(my $i = 0; $i < $numchildren; ++$i) {
    $pid = fork();
    if($pid == 0) {
        last;
    } else {
        print "forked $pid\n";
    }
}
$pid = $$;
print "pid: $pid\n";

sub fetch {
    my $tid = shift;
    my $async = HTTP::Async->new;
    $async->slots(int(@urls));
    my %idurl = ();

    while(1) {
        if($async->total_count < $async->slots) {
            my $url = $urls[int(rand(int(@urls)))];
            chomp $url;
            print "start $pid/$tid: $url\n";
            my $id = $async->add(HTTP::Request->new(GET=>$url));
            $idurl{$id} = $url;
        }
        if($async->not_empty) {
            my ($resp, $id) = $async->next_response();
            if($resp) {
                my $size = length $resp->content;
                my $url = $idurl{$id};
                print "finish $pid/$tid: $url, $size bytes\n";
                delete $idurl{$id};
            }
        }
    }
}

my @threads;
for(my $i = 0; $i < $numthreads; ++$i) {
    my $thread = threads->create(\&fetch,$i);
    push(@threads, $thread);
}
foreach (@threads) {
    $_->join();
}

__DATA__
some urls...