use threads;
use threads::shared;
{
    package A;
    use threads;
    use threads::shared;
    sub new {
        my $class = shift;
    	my $self = &share({});
      	print "Created $class at $self\n";
        return bless $self, $class;
    }
    sub get_s {
    }
    sub DESTROY {
        print "Destroy $_[0]\n";
    }
}

my $a :shared;
$a  = A->new();
for (1..2) {
    async {
        print "thread start\n";
        $a->get_s();
    }->join();
}

##</code><code>##

P:\bin>perl threads_test.cgi
Created A at HASH(0x225800)
thread start
Destroy A=HASH(0x1e07d9c)
thread start
Destroy A=HASH(0x1dbba9c)
Destroy A=HASH(0x225800)

##</code><code>##

package A;
our %created_objs : unique;

sub new {
...
bless $self, $class;
$created_objs{ $self } = 1;
return $self;
}

##</code><code>##

sub DESTROY {
    my $self = shift;
    if ($created_objs{$self}) {
        # do my DESTROY stuff
        delete $created_objs{ $self };
    }
}