Creating the desktop's menu bar takes 1 second

[Federico Mena Quintero <federico ximian com>]

Hi,

I've been taking some more profiles of nautilus startup, and creating
the menu bar for the desktop window takes around 1 second at login time.
Of course, the desktop window has no visible menu bar :)

Digging deeper, the culprit is this:

nautilus_window_initialize_menus {
  ...
  if (!have_burn_uri ()) {    <---- see below
     set_visible (NAUTILUS_ACTION_GO_TO_BURN_CD, FALSE);
  }

have_burn_uri() takes between 0.5 and 1.0 seconds, depending on whether
we get preempted in the middle.  have_burn_uri() is expensive the first
time, because it has to load libmapping.so in order to create a
"burn:///" URI.  In addition, it has to spawn mapping-daemon due to the
module's initialization function.  Given all the churn that happens
during login, this can become really expensive, even with readahead
files.

Ideally, the desktop window shouldn't get a menubar/statusbar created
for it at all.  In the meantime, here's a simple patch to avoid calling
have_burn_uri() for the desktop window.  Is this OK to commit?

  Federico

Index: ChangeLog
===================================================================
RCS file: /cvs/gnome/nautilus/ChangeLog,v
retrieving revision 1.6828
diff -u -p -r1.6828 ChangeLog
--- ChangeLog	13 Mar 2006 10:51:17 -0000	1.6828
+++ ChangeLog	15 Mar 2006 04:41:20 -0000
@@ -1,3 +1,31 @@
+2006-03-14  Federico Mena Quintero  <federico novell com>
+
+	* src/nautilus-window-menus.c: (nautilus_window_initialize_menus):
+	Don't set the visibility of the "burn CD" action here.
+	(nautilus_window_initialize_menus_constructed): New public
+	function.  Only disable NAUTILUS_ACTION_GO_TO_BURN_CD if we are in
+	a window which has a menubar.  This prevents calling
+	have_burn_uri() unnecessarily for the desktop window, as this is
+	an expensive operation during login (up to 1 second!).  The way
+	have_burn_uri() works is by creating a "burn:///" URI and seeing
+	if it is valid, but this makes gnome-vfs load libmapping.so from
+	nautilus-cd-burner; this takes a long time during login.
+
+	* src/nautilus-window-private.h: Added prototype for
+	nautilus_window_initialize_menus_constructed().
+
+	* src/nautilus-window.h: New prototype for
+	nautilus_window_has_menubar_and_statusbar().
+
+	* src/nautilus-window.c
+	(nautilus_window_has_menubar_and_statusbar): New function; returns
+	whether the window should have a menubar and statusbar.  This
+	depends on the window_type from the class structure.
+	(nautilus_window_constructor): Call
+	nautilus_window_initialize_menus_constructed().  We do it here so
+	that its own call to nautilus_window_has_menubar_and_statusbar()
+	will already have the right value for class->window_type.
+
 2006-03-13  Alexander Larsson  <alexl redhat com>
 
 	* configure.in:
Index: src/nautilus-window-menus.c
===================================================================
RCS file: /cvs/gnome/nautilus/src/nautilus-window-menus.c,v
retrieving revision 1.293
diff -u -p -r1.293 nautilus-window-menus.c
--- src/nautilus-window-menus.c	15 Dec 2005 14:25:58 -0000	1.293
+++ src/nautilus-window-menus.c	15 Mar 2006 04:41:21 -0000
@@ -744,12 +744,23 @@ nautilus_window_initialize_menus (Nautil
 	ui = nautilus_ui_string_get ("nautilus-shell-ui.xml");
 	gtk_ui_manager_add_ui_from_string (ui_manager, ui, -1, NULL);
 
-	if (!have_burn_uri ()) {
-		action = gtk_action_group_get_action (action_group, NAUTILUS_ACTION_GO_TO_BURN_CD);
-		gtk_action_set_visible (action, FALSE);
-	}
-
 	nautilus_window_initialize_bookmarks_menu (window);
+}
+
+void
+nautilus_window_initialize_menus_constructed (NautilusWindow *window)
+{
+	GtkAction *action;
+
+	/* Don't call have_burn_uri() for the desktop window, as this is a very
+	 * expensive operation during login (around 1 second) ---
+	 * have_burn_uri() has to create a "burn:///" URI, which causes
+	 * gnome-vfs to link in libmapping.so from nautilus-cd-burner.
+	 */
+	if (nautilus_window_has_menubar_and_statusbar (window) && !have_burn_uri ()) {
+		action = gtk_action_group_get_action (window->details->main_action_group, NAUTILUS_ACTION_GO_TO_BURN_CD);
+ 		gtk_action_set_visible (action, FALSE);
+ 	}
 }
 
 static GList *
Index: src/nautilus-window-private.h
===================================================================
RCS file: /cvs/gnome/nautilus/src/nautilus-window-private.h,v
retrieving revision 1.112
diff -u -p -r1.112 nautilus-window-private.h
--- src/nautilus-window-private.h	3 Mar 2006 13:42:24 -0000	1.112
+++ src/nautilus-window-private.h	15 Mar 2006 04:41:21 -0000
@@ -176,6 +176,7 @@ void               nautilus_window_set_s
 void               nautilus_window_load_view_as_menus                    (NautilusWindow    *window);
 void               nautilus_window_load_extension_menus                  (NautilusWindow    *window);
 void               nautilus_window_initialize_menus                      (NautilusWindow    *window);
+void               nautilus_window_initialize_menus_constructed          (NautilusWindow    *window);
 void               nautilus_menus_append_bookmark_to_menu                (NautilusWindow    *window, 
                                                                           NautilusBookmark  *bookmark, 
                                                                           const char        *parent_path,
Index: src/nautilus-window.c
===================================================================
RCS file: /cvs/gnome/nautilus/src/nautilus-window.c,v
retrieving revision 1.461
diff -u -p -r1.461 nautilus-window.c
--- src/nautilus-window.c	27 Feb 2006 15:51:47 -0000	1.461
+++ src/nautilus-window.c	15 Mar 2006 04:41:21 -0000
@@ -159,7 +159,6 @@ nautilus_window_init (NautilusWindow *wi
 	gtk_widget_show (table);
 	gtk_container_add (GTK_CONTAINER (window), table);
 
-
 	statusbar = gtk_statusbar_new ();
 	window->details->statusbar = statusbar;
 	gtk_table_attach (GTK_TABLE (table),
@@ -642,6 +641,25 @@ nautilus_window_finalize (GObject *objec
 	G_OBJECT_CLASS (nautilus_window_parent_class)->finalize (object);
 }
 
+static GObject *
+nautilus_window_constructor (GType type,
+			     guint n_construct_properties,
+			     GObjectConstructParam *construct_params)
+{
+	GObject *object;
+	NautilusWindow *window;
+
+	object = (* G_OBJECT_CLASS (nautilus_window_parent_class)->constructor) (type,
+										 n_construct_properties,
+										 construct_params);
+
+	window = NAUTILUS_WINDOW (object);
+
+	nautilus_window_initialize_menus_constructed (window);
+
+	return object;
+}
+
 void
 nautilus_window_show_window (NautilusWindow *window)
 {
@@ -1532,8 +1550,9 @@ static void
 nautilus_window_class_init (NautilusWindowClass *class)
 {
 	GtkBindingSet *binding_set;
-	
+
 	G_OBJECT_CLASS (class)->finalize = nautilus_window_finalize;
+	G_OBJECT_CLASS (class)->constructor = nautilus_window_constructor;
 	G_OBJECT_CLASS (class)->get_property = nautilus_window_get_property;
 	G_OBJECT_CLASS (class)->set_property = nautilus_window_set_property;
 	GTK_OBJECT_CLASS (class)->destroy = nautilus_window_destroy;
@@ -1602,4 +1621,20 @@ nautilus_window_class_init (NautilusWind
 			     "\n"
 			     "    widget \"*.nautilus-extra-view-widget\" style:rc \"nautilus-extra-view-widgets-style-internal\" \n"
 			     "\n");
+}
+
+/**
+ * nautilus_window_has_menubar_and_statusbar:
+ * @window: A #NautilusWindow
+ * 
+ * Queries whether the window should have a menubar and statusbar, based on the
+ * window_type from its class structure.
+ * 
+ * Return value: TRUE if the window should have a menubar and statusbar; FALSE
+ * otherwise.
+ **/
+gboolean
+nautilus_window_has_menubar_and_statusbar (NautilusWindow *window)
+{
+	return (nautilus_window_get_window_type (window) != NAUTILUS_WINDOW_DESKTOP);
 }
Index: src/nautilus-window.h
===================================================================
RCS file: /cvs/gnome/nautilus/src/nautilus-window.h,v
retrieving revision 1.125
diff -u -p -r1.125 nautilus-window.h
--- src/nautilus-window.h	27 Feb 2006 15:51:47 -0000	1.125
+++ src/nautilus-window.h	15 Mar 2006 04:41:21 -0000
@@ -150,5 +150,6 @@ void             nautilus_window_allow_b
 GtkUIManager *   nautilus_window_get_ui_manager       (NautilusWindow    *window);
 void             nautilus_window_add_extra_location_widget (NautilusWindow  *window,
                                                             GtkWidget       *widget);
+gboolean         nautilus_window_has_menubar_and_statusbar (NautilusWindow *window);
 
 #endif