This seems like a similar problem to Optimized remote ping in particular Re: Optimized remote ping which was something I did before joining perlmonks. It essentially does what an async framework would do (all in one process).

Here's a slightly updated version: 

#!/usr/bin/perl

# http://perlmonks.org/?node_id=1135109
# http://perlmonks.org/?node_id=11103970

use strict;
use warnings;
use IO::Socket;
use IO::Select;

my @ips = map "192.168.1.$_", 1..20; # your IPs here
my $port = 22; # your port here
my $max = 500; # somewhat smaller than max "open files"

my %handles;
my $sel = IO::Select->new;

while( @ips or $sel->count )
  {
  if( @ips and $sel->count < $max )
    {
    my $ip = shift @ips;
    my $fh = IO::Socket::INET->new(PeerHost => $ip, PeerPort => $port,
      Proto => 'tcp', Blocking => 0);
    $handles{$fh} = "$ip:$port"; 
    $sel->add($fh);
    }
  elsif( @ips ? $sel->count >= $max : $sel->count )
    {
    for my $fh ( $sel->can_write )
      {
      print $fh->connected ? '   ' : 'not', " alive  $handles{$fh}\n";
      $sel->remove($fh);
      delete $handles{$fh};
      }
    }
  }

[download]

In reply to Re: A question of fork efficiency by tybalt89
in thread A question of fork efficiency by synless

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