I've been toying around with modules, and with Tk I know you need to reuse a module's object's namespace, or you get a memory gain. So I decided to try and simplify it to it's simplest form, to see what is going on. So in the examples below, if I use a straight hash to store data, I can load, empty, and reuse the hash with no memory gain on the second load.

With a module however, no matter what I do, the "new" causes quite a memory gain on the second use, even if I try to load the objects into a reusable hash. So, I'm sure this is a common question, but is there a way to completely return a destroyed objects memory, so it can be reused? Or is there just an unavoidable penalty for creating a new namespace? 

#this is a pure hash, and it works as I expect

#!/usr/bin/perl
use warnings;
use strict;

my %bubs;

for(1.. 500){
  $bubs{$_}{'stuff'} = [1..1000];
  print "adding $_\n";
}

<>;

for(1.. 500){
  $bubs{$_}=();
  delete $bubs{$_};
  print "deleting $_\n";
}

<>;

for(1.. 500){
  $bubs{$_}{'stuff'} = [1..1000];
   print "adding $_\n";
}

for(1.. 500){
  $bubs{$_}=();
  delete $bubs{$_};
   print "deleting $_\n";
}

<>;
__END__

####################################
# this is with objects, where it dosn't
# reuse a DESTROYED objects space even though I
# stuff them into the same hash space
#!/usr/bin/perl
use warnings;
use strict;

my %bubs;

for(1.. 500){
  $bubs{$_} = ZtkBubject->new(
                 -name => $_,
          );
 $bubs{$_}->DESTROY;
 delete $bubs{$_};
 $bubs{$_}=();
}

<>;

for(1.. 500){
  $bubs{$_} = ZtkBubject->new(
                 -name => $_,
          );
 $bubs{$_}->DESTROY;
}

<>;

#=====================================================================
+======== 
#                ZtkBubject  Class 
#=====================================================================
+======== 
package ZtkBubject;
use strict 'vars';
use Carp;

sub new {
    my ($class, %arg) = @_;

      # object attributes 
      my $self = {
          'name'  => $arg{-name},         #identifying name  
       };
bless $self;

#    print "just blessed $self\n"; 
    $self->{self} = $self;
    $self->{stuff} = [1..1000]; #add some memory usage  

return $self;
}
############################################# 
sub DESTROY{
  my ($self) = @_;
   print "destroying->", $self->{name},'  ',$self,"\n";
}
########################################### 
1;
__END__

[download]

I'm not really a human, but I play one on earth. flash japh

2004-12-29 Janitored by Arunbear - added readmore tags, as per Monastery guidelines

In reply to Is there a penalty for namespace use? by zentara

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.