From: David Espada <davinciSINSPAM@...>
Date: 2005-01-18T18:01:10+09:00
Subject: [ruby-gtk2] Garbage collection and memory use

 Hi all.

 Look at next script:

----------------------------------------
#!/usr/bin/ruby

require 'glib2'
require 'gtk2'

def bucle
	1000.times do |i|
		100.times do |j|
			p i
			p j
			p '******'
			v = Gtk::Window.new.show_all
			v.destroy
		end
		GC.start
	end
end

Gtk::init

ventana = Gtk::Window.new
ventana.set_title("Creating windows")
ventana.signal_connect('delete_event') {exit}


vbox = Gtk::VBox::new(true, 10)

boton = Gtk::Button.new('_start', true)
boton.signal_connect('clicked') do bucle end
vbox.pack_start(boton, true, true, 0)

ventana.add(vbox)

ventana.show_all

Gtk.main
--------------------------------------------

 When you push button, it triggers a loop that creates and destroy a
 Gtk2 window in each iteration. For each 1000 iters, I call GC.start in
 order to run Garbage Collection.

 In theory, there is no single variable that persist from one iter to
 next, and garbage collection should reget memory for more use, without
 collapsing physical memory and swap space.

 But that is what happens actually, and I don't know the reason.

 You can say that this lanscape is very rare and not reproducible in
 practice, but I have an application that creates and destroys windows
 with many widgets, and it loads system until swaping is constant,
 slowing work of my users.

 What is problem with Garbage Collection? Why it doesn't free memory
 althought I invoque it explicitly? Any clue or solution that doesn't
 force me to change all code in order to reuse windows instead of
 create them when I need?

 I am in the very edge, but it seems that Ruby Garbage Collection
 doesn't work properly with Gtk2 widgets, because memory is not freed.

 Thanks for your ideas and help.

 I use last version of Ruby (1.8.2) with last version of Ruby-gtk2
 (0.11.0) in Linux Debian Sid, with kernel 2.6.7.

 Greets.

 							David