our %planets : shared;
our $response = SomeClass::TCP_IP_Response->new(@some_arguments);
[...]
lock %planets;
if (exists $planets{$some_id}) {
   lock $planets{$some_id};
   $response->content($planets{$some_id}->{'data'});
   $planets{$some_id}->{'atime'} = time;
}
else {
   my $data;
   [...] # read the serialized data from disk
   my %el = ( 'data' => $data,
              'atime' => time,
              'deleted' => 0,
              'modified' => 0
            );
   $planets{$some_id} = share(%el);
}