show and hide increase memory, too

memtest2.pl

#!/usr/bin/perl
use strict;
use warnings FATAL => 'all';
use 5.10.1;
use autodie;

use constant {GAUGE => '▪'};

sub on_start {
    my ($self) = @_;

    my $rend = urxvt::OVERLAY_RSTYLE;
       $rend = urxvt::SET_BGCOLOR $rend, 1;
       $rend = urxvt::SET_FGCOLOR $rend, 255;
   
    $self->{netOverlay} = $self->overlay ( -1, 0, 1, 1, $rend, 0 );
    $self->{netOverlay}->set ( 0, 0, GAUGE );

    $self->{net} = urxvt::timer
        ->new
        ->start ( 1 + int urxvt::NOW )
        ->interval ( 1 )
        ->cb ( sub {
        for (1..1000) {
            $self->{netOverlay}->hide;
            $self->{netOverlay}->show;
        }
        } );
    ()
}