Thanks for your help. This is how i solved the problem: 
#!/usr/bin/perl -w

use strict;

use constant WIDTH    => 1000;
use constant HEIGHT    => 100;
use constant SPEED    => 1;

use Cairo;
use Glib qw(TRUE FALSE);
use Gtk2 -init;
use Gtk2::Pango;

my ($text,$ticks, $cr, $layout, $desc, $area);

sub initialize {
    $cr = Gtk2::Gdk::Cairo::Context -> create($area->window());
    $layout = Gtk2::Pango::Cairo::create_layout($cr);
    $desc = Gtk2::Pango::FontDescription -> from_string("Sans Bold 57"
+);
    $layout -> set_font_description($desc);
    $layout->set_alignment("PANGO_ALIGN_LEFT");
}

sub draw_text {
    $cr->push_group;    
    $layout->set_text($text);


    Gtk2::Pango::Cairo::update_layout($cr, $layout);

    my @size = $layout->get_pixel_size;
    
    $cr -> translate(-($ticks*SPEED)%$size[0],0);

    $cr->set_source_rgb(1.0,1.0,1.0);
    $cr->fill();
    $cr -> set_source_rgb(0.0,0.0,0.0);
    
    my $count = int(WIDTH/$size[0]);
    
    $cr->translate(-$size[0]*2,0);
    
    for(my $i = 0; $i<=$count+1; $i++){
        $cr->translate($size[0],0);
        Gtk2::Pango::Cairo::show_layout($cr,$layout);
    }
    $cr->pop_group_to_source;
    $cr->paint;
}

my $window = Gtk2::Window->new();
$window -> signal_connect(delete_event => sub {
    Gtk2 -> main_quit();
});

$area = Gtk2::DrawingArea -> new();

sub draw {
    $cr->rectangle(0,0,WIDTH,HEIGHT);
    draw_text($cr,$ticks);
}


sub timer {
    $ticks ++;
    draw();
    return 1;
}


$text = 'Please specify your input file';
if($ARGV[0]){
    open(INPUT_FILE, "$ARGV[0]");
    $text = <INPUT_FILE>;
}

$ticks = 0;

$window -> set_default_size(WIDTH,HEIGHT);
$window -> add($area);

$window->show_all();

initialize;
my $timer = Glib::Timeout->add(1000/60, \&timer ,'',);
Gtk2->main();

[download]
Was it Perl or GTK2 libraries bug with releasing objects after each timer callback? Should I avoid creating local (my) objects in subs?

In reply to Re: Bad, bad memory leaks in simple script by Solak
in thread Bad, bad memory leaks in simple script [solved] by Solak

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