POE-Tk memory leak?

flw <[email protected]> Sat, 7 Mar 2009 12:02:40 +0800

Newsgroups	gmane.comp.lang.perl.poe
Message-ID	<[email protected]>

Hello all,

I have a trouble about Tk interfaces in POE.

http://poe.perl.org/?POE_Cookbook/Tk_Interfaces
When I run above POE-Tk example on my person computer,
there has been a rapid increase in the memory usage of perl.exe process.
More than 300MB memory leaked in two minutes, it's so shocking for me.

How to debug and fix it?

Attachment is the test code.

Any advice will be appreciated.
Thanks in advance.

poetk.pl (application/octet-stream, 2 KB)

#!/usr/bin/perl 

use strict;
use warnings;

use Tk;
use POE;

# Create the session that will drive the user interface.

POE::Session->create
  ( inline_states =>
      { _start => \&ui_start,
        ev_count => \&ui_count,
        ev_clear => \&ui_clear,
      }
  );

# Run the program until it is exited.

$poe_kernel->run();
exit 0;

# Create the user interface when the session starts.  This assumes
# some familiarity with Tk.  ui_start() illustrates four important
# points.
#
# 1. Tk events require a main window.  POE creates one for internal
# use and exports it as $poe_main_window.  ui_start() uses that as the
# basis for its user interface.
#
# 2. Widgets we need to work with later, such as the counter display,
# must be stored somewhere.  The heap is a convenient place for them.
#
# 3. Tk widgets expect callbacks in the form of coderefs.  The
# session's postback() method provides coderefs that post events when
# called.  The Button created in ui_start() fires an "ev_clear" event
# when it is pressed.
#
# 4. POE::Kernel methods such as yield(), post(), delay(), signal(),
# and select() (among others) work the same as they would without Tk.
# This feature makes it possible to write back end sessions that
# support multiple GUIs with a single code base.

sub ui_start {
    my ( $kernel, $session, $heap ) = @_[ KERNEL, SESSION, HEAP ];

    $poe_main_window->Label( -text => "Counter" )->pack;

    $heap->{counter_widget} =
      $poe_main_window->Label( -textvariable => \$heap->{counter} )->pack;

    $poe_main_window->Button
      ( -text => "Clear",
        -command => $session->postback("ev_clear")
      )->pack;

    $kernel->yield("ev_count");
}

# Handle the "ev_count" event by increasing a counter and displaying
# its new value.

sub ui_count {
    $_[HEAP]->{counter}++;
    $_[KERNEL]->yield("ev_count");
}

# Handle the "ev_clear" event by clearing and redisplaying the
# counter.

sub ui_clear {
    $_[HEAP]->{counter} = 0;
}