POE mysteriously exits

[Daisuke Maki]

Hi all

I'd like some advise on how to debug a POE application (a mid-sized web
crawler) that is seemingly exiting sporadically without displaying any
error conditions. The program runs randomly for 10 minutes ~ 4,5 hours,
and then exists without showing any meaningful error message.

through using TRACE_DEFAULT() and inserting a bunch of print statements,
I've traced this down to circa line 924 of POE::Kernel:

  my $return;
  if (wantarray) {
    $return = [
      $session->_invoke_state($source_session, $event, $etc, $file, $line,
        $fromstate)
    ];
  }
  else {
    $return =
      $session->_invoke_state($source_session, $event, $etc, $file, $line,
        $fromstate);
  }

The execution goes into the else cluase, but _invoke_state is never
called!!!

I added debug statements like so in POE::Kernel

  my $return;
  if (wantarray) {
    $return = [
      $session->_invoke_state($source_session, $event, $etc, $file, $line,
        $fromstate)
    ];
  }
  else {
_warn("DEBUG(1): $session, $source_session, $event, $etc, $file, $line,
$fromstate");
    $return =
      $session->_invoke_state($source_session, $event, $etc, $file, $line,
        $fromstate);
_warn("DEBUG(3): _invoke_state done");
  }

As well as

sub _invoke_state {
  my ($self, $source_session, $event, $etc) = @_;
_warn("DEBUG(2) _invoke_state");

But the execution never reaches DEBUG(2). I'm at a complete loss as to
what to do now. Has anyone hit anything like this?

As far as POE related modules go, I'm using
   POE - 0.3009
   POE::Component::Client::HTTP - 0.65
   POE::Component::Client::DNS - 0.98

Any help is appreciated.

---d