From 1fee4971f41ae1d9ade6c438ea613901319b6e45 Mon Sep 17 00:00:00 2001
From: Benny Malengier <benny.malengier@gramps-project.org>
Date: Sun, 31 Oct 2010 07:33:17 +0000
Subject: [PATCH] 4333: memory leak in 3.2

svn: r16089
---
 src/Lru.py                                   |  3 +
 src/gen/db/read.py                           | 26 +++++-
 src/gen/db/undoredo.py                       |  4 +
 src/gen/db/write.py                          | 21 ++++-
 src/gen/utils/callback.py                    | 13 ++-
 src/gen/utils/configmanager.py               | 16 ++--
 src/gui/editors/displaytabs/nameembedlist.py | 10 +++
 src/gui/editors/editfamily.py                |  9 +++
 src/gui/editors/editname.py                  | 16 ++--
 src/gui/editors/editperson.py                | 19 ++++-
 src/gui/editors/editprimary.py               | 17 +++-
 src/gui/editors/editsecondary.py             | 14 +++-
 src/gui/views/listview.py                    |  3 +
 src/gui/views/treemodels/eventmodel.py       | 11 +++
 src/gui/views/treemodels/familymodel.py      | 11 +++
 src/gui/views/treemodels/flatbasemodel.py    | 20 +++++
 src/gui/views/treemodels/mediamodel.py       | 11 +++
 src/gui/views/treemodels/notemodel.py        | 11 +++
 src/gui/views/treemodels/peoplemodel.py      | 28 ++++++-
 src/gui/views/treemodels/placemodel.py       | 26 ++++++
 src/gui/views/treemodels/repomodel.py        | 12 +++
 src/gui/views/treemodels/sourcemodel.py      | 11 +++
 src/gui/views/treemodels/treebasemodel.py    | 20 +++++
 src/gui/widgets/buttons.py                   | 25 ++++++
 src/gui/widgets/monitoredwidgets.py          | 83 ++++++++++++++++++++
 25 files changed, 416 insertions(+), 24 deletions(-)

diff --git a/src/Lru.py b/src/Lru.py
index 4928cbc1f..c35dc3fed 100644
--- a/src/Lru.py
+++ b/src/Lru.py
@@ -151,4 +151,7 @@ class LRU(object):
         """
         Empties LRU
         """
+        for obj, node in self.data.iteritems():
+            node.prev = None
+            node.next = None
         self.data.clear()
diff --git a/src/gen/db/read.py b/src/gen/db/read.py
index 7631aac1f..6bbdace68 100644
--- a/src/gen/db/read.py
+++ b/src/gen/db/read.py
@@ -129,6 +129,9 @@ class DbBookmarks(object):
     def insert(self, pos, item):
         self.bookmarks.insert(pos, item)
 
+    def close(self):
+        del self.bookmarks
+
 #-------------------------------------------------------------------------
 #
 # GrampsDBReadCursor
@@ -206,7 +209,6 @@ class DbBsddbRead(DbReadBase, Callback):
         """
         Create a new DbBsddbRead instance. 
         """
-        
         DbReadBase.__init__(self)
         Callback.__init__(self)
 
@@ -427,8 +429,26 @@ class DbBsddbRead(DbReadBase, Callback):
         
         The method needs to be overridden in the derived class.
         """
-        pass
-        
+        #remove circular dependance
+        self.basedb = None
+        #remove links to functions
+        self.disconnect_all()
+        for key in self._tables:
+            for subkey in self._tables[key]:
+                self._tables[key][subkey] = None
+            del self._tables[key][subkey]
+            self._tables[key] = None
+        del self._tables
+##        self.bookmarks = None
+##        self.family_bookmarks = None
+##        self.event_bookmarks = None
+##        self.place_bookmarks = None
+##        self.source_bookmarks = None
+##        self.repo_bookmarks = None
+##        self.media_bookmarks = None
+##        self.note_bookmarks = None
+
+
     def is_open(self):
         """
         Return 1 if the database has been opened.
diff --git a/src/gen/db/undoredo.py b/src/gen/db/undoredo.py
index 0ffa394e0..134863dd4 100644
--- a/src/gen/db/undoredo.py
+++ b/src/gen/db/undoredo.py
@@ -400,6 +400,10 @@ class DbUndoBSDDB(DbUndo):
         Close the undo/redo database
         """
         self.undodb.close()
+        self.undodb = None
+        self.mapbase = None
+        self.db = None
+        
         try:
             os.remove(self.path)
         except OSError:
diff --git a/src/gen/db/write.py b/src/gen/db/write.py
index f0485d1d1..71c7a93fb 100644
--- a/src/gen/db/write.py
+++ b/src/gen/db/write.py
@@ -1013,7 +1013,6 @@ class DbBsddb(DbBsddbRead, DbWriteBase, UpdateCallback):
     def close(self):
         if not self.db_is_open:
             return
-
         self.env.txn_checkpoint()
 
         self.__close_metadata()
@@ -1060,6 +1059,26 @@ class DbBsddb(DbBsddbRead, DbWriteBase, UpdateCallback):
         self.env            = None
         self.metadata       = None
         self.db_is_open     = False
+        self.surname_lis = None
+        
+        DbBsddbRead.close(self)
+        
+        self.person_map = None
+        self.family_map = None
+        self.repository_map = None
+        self.note_map = None
+        self.place_map = None
+        self.source_map = None
+        self.media_map = None
+        self.event_map = None
+        self.tag_map = None
+        self.reference_map_primary_map = None
+        self.reference_map_referenced_map = None
+        self.reference_map = None
+        self.undo_callback = None
+        self.redo_callback = None
+        self.undo_history_callback = None
+        self.undodb = None
 
         try:
             clear_lock_file(self.get_save_path())
diff --git a/src/gen/utils/callback.py b/src/gen/utils/callback.py
index 04c98878d..50eaa031e 100644
--- a/src/gen/utils/callback.py
+++ b/src/gen/utils/callback.py
@@ -40,6 +40,7 @@ import sys
 import types
 import traceback
 import inspect
+import copy
 
 log = sys.stderr.write
 
@@ -311,8 +312,16 @@ class Callback(object):
                               ": %s with key: %s\n" % (signal_name, 
                                                        str(key)))
                     self.__callback_map[signal_name].remove(cb)
-                    
-                    
+
+    def disconnect_all(self):# Find the key in the callback map.
+        for signal_name in self.__callback_map:
+            keymap = copy.copy(self.__callback_map[signal_name])
+            for key in keymap:
+                self.__callback_map[signal_name].remove(key)
+            self.__callback_map[signal_name] = None
+        self.__callback_map = None
+        del self.__callback_map
+
     def emit(self, signal_name, args=tuple()):
         """
         Emit the signal called signal_name. The args must be a tuple of
diff --git a/src/gen/utils/configmanager.py b/src/gen/utils/configmanager.py
index b73d5c1fd..9aaf129d3 100644
--- a/src/gen/utils/configmanager.py
+++ b/src/gen/utils/configmanager.py
@@ -38,14 +38,18 @@ import ConfigParser
 import errno
 import copy
 
-try:
-    from ast import literal_eval as safe_eval
-except:
-    # PYTHON2.5 COMPATIBILITY: no ast present
-    # not as safe as literal_eval, but works for python2.5:
-    def safe_eval(exp):
+def safe_eval(exp):
         # restrict eval to empty environment
         return eval(exp, {})
+##try:
+##    from ast import literal_eval as safe_eval
+##    # this leaks memory !!
+##except:
+##    # PYTHON2.5 COMPATIBILITY: no ast present
+##    # not as safe as literal_eval, but works for python2.5:
+##    def safe_eval(exp):
+##        # restrict eval to empty environment
+##        return eval(exp, {})
 
 #---------------------------------------------------------------
 #
diff --git a/src/gui/editors/displaytabs/nameembedlist.py b/src/gui/editors/displaytabs/nameembedlist.py
index 44ff97a0d..657f3b06a 100644
--- a/src/gui/editors/displaytabs/nameembedlist.py
+++ b/src/gui/editors/displaytabs/nameembedlist.py
@@ -78,6 +78,8 @@ class NameEmbedList(GroupEmbeddedList):
         ]
     
     def __init__(self, dbstate, uistate, track, data, person, callback):
+        """callback is the function to call when preferred name changes
+           on the namelist """
         self.data = data
         self.person = person
         self.callback = callback
@@ -86,6 +88,14 @@ class NameEmbedList(GroupEmbeddedList):
                               NameModel, move_buttons=True)
         self.tree.expand_all()
 
+    def _cleanup_on_exit(self):
+        """Unset all things that can block garbage collection.
+        Finalize rest
+        """
+        self.person = None
+        self.callback = None
+        self.data = None
+
     def get_data(self):
         return ([self.person.get_primary_name()], 
                  self.data)
diff --git a/src/gui/editors/editfamily.py b/src/gui/editors/editfamily.py
index 639b670b9..3b2f0ab40 100644
--- a/src/gui/editors/editfamily.py
+++ b/src/gui/editors/editfamily.py
@@ -448,6 +448,15 @@ class EditFamily(EditPrimary):
         else:
             self.add_parent = False
 
+    def _cleanup_on_exit(self):
+        """Unset all things that can block garbage collection.
+        Finalize rest
+        """
+        #FIXME, we rebind show_all below, this prevents garbage collection of
+        #  the dialog, fix the rebind
+        self.window.show_all = None
+        EditPrimary._cleanup_on_exit(self)
+
     def empty_object(self):
         return gen.lib.Family()
 
diff --git a/src/gui/editors/editname.py b/src/gui/editors/editname.py
index a80cade52..1cf6267a7 100644
--- a/src/gui/editors/editname.py
+++ b/src/gui/editors/editname.py
@@ -267,16 +267,17 @@ class EditName(EditSecondary):
         notebook = self.top.get_object("notebook")
 
         self._add_tab(notebook, self.gennam)
+        self.track_ref_for_deletion("gennam")
 
-        self.srcref_list = self._add_tab(
-            notebook,
-            SourceEmbedList(self.dbstate,self.uistate,self.track,self.obj))
+        self.srcref_list = SourceEmbedList(self.dbstate,self.uistate,self.track,self.obj)
+        self._add_tab(notebook, self.srcref_list)
+        self.track_ref_for_deletion("srcref_list")
         
-        self.note_tab = self._add_tab(
-            notebook,
-            NoteTab(self.dbstate, self.uistate, self.track,
+        self.note_tab = NoteTab(self.dbstate, self.uistate, self.track,
                     self.obj.get_note_list(),
-                    notetype=NoteType.PERSONNAME))
+                    notetype=NoteType.PERSONNAME)
+        self._add_tab(notebook, self.note_tab)
+        self.track_ref_for_deletion("note_tab")
 
         self._setup_notebook_tabs( notebook)
         
@@ -442,6 +443,7 @@ class EditName(EditSecondary):
         if closeit:
             if self.callback:
                 self.callback(self.obj)
+            self.callback = None
             self.close()
 
     def _cleanup_on_exit(self):
diff --git a/src/gui/editors/editperson.py b/src/gui/editors/editperson.py
index 15d872dd0..b3afea7cb 100644
--- a/src/gui/editors/editperson.py
+++ b/src/gui/editors/editperson.py
@@ -854,6 +854,7 @@ class EditPerson(EditPrimary):
         self.close()
         if self.callback:
             self.callback(self.obj)
+        self.callback = None
 
     def _edit_name_clicked(self, obj):
         """
@@ -1017,7 +1018,23 @@ class EditPerson(EditPrimary):
         return child_ref_list
 
     def _cleanup_on_exit(self):
-        pass
+        """Unset all things that can block garbage collection.
+        Finalize rest
+        """
+##        self.private.destroy()
+##        self.gender.destroy()
+##        self.ntype_field.destroy()
+##        self.given.destroy()
+##        self.call.destroy()
+##        self.title.destroy()
+##        self.suffix.destroy()
+##        self.nick.destroy()
+##        self.surname_field.destroy()
+##        self.prefix.destroy()
+##        self.ortype_field.destroy()
+##        self.tags.destroy()
+##        self.gid.destroy()
+        EditPrimary._cleanup_on_exit(self)
         #config.save()
 
 
diff --git a/src/gui/editors/editprimary.py b/src/gui/editors/editprimary.py
index b6ca9a764..6aa9e1bf6 100644
--- a/src/gui/editors/editprimary.py
+++ b/src/gui/editors/editprimary.py
@@ -151,7 +151,13 @@ class EditPrimary(ManagedWindow.ManagedWindow, DbGUIElement):
         return page
 
     def _cleanup_on_exit(self):
-        pass
+        """Unset all things that can block garbage collection.
+        Finalize rest
+        """
+        for tab in self.__tabs:
+            if hasattr(tab, '_cleanup_on_exit'):
+                tab._cleanup_on_exit()
+        self.__tabs = None
 
     def object_is_empty(self):
         return cmp(self.obj.serialize()[1:],
@@ -173,7 +179,12 @@ class EditPrimary(ManagedWindow.ManagedWindow, DbGUIElement):
         self._cleanup_db_connects()
         self.dbstate.disconnect(self.dbstate_connect_key)
         self._cleanup_on_exit()
+        self.get_from_handle = None
+        self.get_from_gramps_id = None
         ManagedWindow.ManagedWindow.close(self)
+        self.dbstate = None
+        self.uistate = None
+        self.db = None
 
     def _cleanup_db_connects(self):
         """
@@ -236,7 +247,9 @@ class EditPrimary(ManagedWindow.ManagedWindow, DbGUIElement):
                        self.obj.serialize()[1:]) != 0
 
     def save(self, *obj):
-        pass
+        """ Save changes and close. Inheriting classes must implement this
+        """
+        self.close()
         
     def set_contexteventbox(self, eventbox):
         """Set the contextbox that grabs button presses if not grabbed
diff --git a/src/gui/editors/editsecondary.py b/src/gui/editors/editsecondary.py
index cae0401ad..a2c4414d9 100644
--- a/src/gui/editors/editsecondary.py
+++ b/src/gui/editors/editsecondary.py
@@ -107,7 +107,19 @@ class EditSecondary(ManagedWindow.ManagedWindow, DbGUIElement):
         return page
 
     def _cleanup_on_exit(self):
-        pass
+        """Unset all things that can block garbage collection.
+        Finalize rest
+        """
+        for tab in self.__tabs:
+            if hasattr(tab, '_cleanup_on_exit'):
+                tab._cleanup_on_exit()
+        self.__tabs = None
+        self.dbstate = None
+        self.uistate = None
+        self.obj = obj
+        self.db = None
+        self.callman.database = None
+        self.callman = None
 
     def define_ok_button(self,button,function):
         button.connect('clicked',function)
diff --git a/src/gui/views/listview.py b/src/gui/views/listview.py
index 41d85a7cf..d971cc5e5 100644
--- a/src/gui/views/listview.py
+++ b/src/gui/views/listview.py
@@ -262,6 +262,9 @@ class ListView(NavigationView):
                 filter_info = (False, value, value[0] in self.exact_search())
 
             if self.dirty or not self.model:
+                if self.model:
+                    self.list.set_model(None)
+                    self.model.destroy()
                 self.model = self.make_model(self.dbstate.db, self.sort_col, 
                                              search=filter_info,
                                              sort_map=self.column_order())
diff --git a/src/gui/views/treemodels/eventmodel.py b/src/gui/views/treemodels/eventmodel.py
index 40425a2e2..d7e7e5c7a 100644
--- a/src/gui/views/treemodels/eventmodel.py
+++ b/src/gui/views/treemodels/eventmodel.py
@@ -99,6 +99,17 @@ class EventModel(FlatBaseModel):
         FlatBaseModel.__init__(self, db, scol, order, tooltip_column=8,
                            search=search, skip=skip, sort_map=sort_map)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.db = None
+        self.gen_cursor = None
+        self.map = None
+        self.fmap = None
+        self.smap = None
+        FlatBaseModel.destroy(self)
+
     def on_get_n_columns(self):
         return len(self.fmap)+1
 
diff --git a/src/gui/views/treemodels/familymodel.py b/src/gui/views/treemodels/familymodel.py
index c4863a921..cc9829b27 100644
--- a/src/gui/views/treemodels/familymodel.py
+++ b/src/gui/views/treemodels/familymodel.py
@@ -89,6 +89,17 @@ class FamilyModel(FlatBaseModel):
         FlatBaseModel.__init__(self, db, scol, order, tooltip_column=9, 
                            search=search, skip=skip, sort_map=sort_map)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.db = None
+        self.gen_cursor = None
+        self.map = None
+        self.fmap = None
+        self.smap = None
+        FlatBaseModel.destroy(self)
+
     def color_column(self):
         """
         Return the color column.
diff --git a/src/gui/views/treemodels/flatbasemodel.py b/src/gui/views/treemodels/flatbasemodel.py
index a6ce7bdb3..f1599f81a 100644
--- a/src/gui/views/treemodels/flatbasemodel.py
+++ b/src/gui/views/treemodels/flatbasemodel.py
@@ -122,6 +122,14 @@ class FlatNodeMap(object):
         self._reverse = False
         self.__corr = (0, 1)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self._index2hndl = None
+        self._fullhndl = None
+        self._hndl2index = None
+
     def set_path_map(self, index2hndllist, fullhndllist, identical=True,
                      reverse=False):
         """
@@ -408,6 +416,18 @@ class FlatBaseModel(gtk.GenericTreeModel):
         _LOG.debug(self.__class__.__name__ + ' __init__ ' +
                     str(time.clock() - cput) + ' sec')
 
+    def destroy(self):
+        """
+        Unset all elements that prevent garbage collection
+        """
+        self.db = None
+        self.sort_func = None
+        if self.node_map:
+            self.node_map.destroy()
+        self.node_map = None
+        self.rebuild_data = None
+        self.search = None
+
     def set_search(self, search):
         """
         Change the search function that filters the data in the model. 
diff --git a/src/gui/views/treemodels/mediamodel.py b/src/gui/views/treemodels/mediamodel.py
index 21c750877..7ba1fcaae 100644
--- a/src/gui/views/treemodels/mediamodel.py
+++ b/src/gui/views/treemodels/mediamodel.py
@@ -89,6 +89,17 @@ class MediaModel(FlatBaseModel):
         FlatBaseModel.__init__(self, db, scol, order, tooltip_column=9,
                            search=search, skip=skip, sort_map=sort_map)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.db = None
+        self.gen_cursor = None
+        self.map = None
+        self.fmap = None
+        self.smap = None
+        FlatBaseModel.destroy(self)
+
     def color_column(self):
         """
         Return the color column.
diff --git a/src/gui/views/treemodels/notemodel.py b/src/gui/views/treemodels/notemodel.py
index 99631b83d..d3ecc400a 100644
--- a/src/gui/views/treemodels/notemodel.py
+++ b/src/gui/views/treemodels/notemodel.py
@@ -79,6 +79,17 @@ class NoteModel(FlatBaseModel):
         FlatBaseModel.__init__(self, db, scol, order, search=search,
                            skip=skip, sort_map=sort_map)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.db = None
+        self.gen_cursor = None
+        self.map = None
+        self.fmap = None
+        self.smap = None
+        FlatBaseModel.destroy(self)
+
     def color_column(self):
         """
         Return the color column.
diff --git a/src/gui/views/treemodels/peoplemodel.py b/src/gui/views/treemodels/peoplemodel.py
index 080551f7f..21f682fd5 100644
--- a/src/gui/views/treemodels/peoplemodel.py
+++ b/src/gui/views/treemodels/peoplemodel.py
@@ -147,6 +147,17 @@ class PeopleBaseModel(object):
         self.lru_bdate = LRU(PeopleBaseModel._CACHE_SIZE)
         self.lru_ddate = LRU(PeopleBaseModel._CACHE_SIZE)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.db = None
+        self.gen_cursor = None
+        self.map = None
+        self.fmap = None
+        self.smap = None
+        self.clear_local_cache()
+
     def color_column(self):
         """
         Return the color column.
@@ -461,7 +472,6 @@ class PersonListModel(PeopleBaseModel, FlatBaseModel):
     """
     def __init__(self, db, scol=0, order=gtk.SORT_ASCENDING, search=None,
                  skip=set(), sort_map=None):
-
         PeopleBaseModel.__init__(self, db)
         FlatBaseModel.__init__(self, db, search=search, skip=skip,
                                 tooltip_column=13,
@@ -471,6 +481,13 @@ class PersonListModel(PeopleBaseModel, FlatBaseModel):
         """ Clear the LRU cache """
         PeopleBaseModel.clear_local_cache(self, handle)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        PeopleBaseModel.destroy(self)
+        FlatBaseModel.destroy(self)
+
 class PersonTreeModel(PeopleBaseModel, TreeBaseModel):
     """
     Hierarchical people model.
@@ -482,6 +499,15 @@ class PersonTreeModel(PeopleBaseModel, TreeBaseModel):
         TreeBaseModel.__init__(self, db, 13, search=search, skip=skip,
                                 scol=scol, order=order, sort_map=sort_map)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        PeopleBaseModel.destroy(self)
+        self.hmap = None
+        self.number_items = None
+        TreeBaseModel.destroy(self)
+
     def _set_base_data(self):
         """See TreeBaseModel, we also set some extra lru caches
         """
diff --git a/src/gui/views/treemodels/placemodel.py b/src/gui/views/treemodels/placemodel.py
index 815478534..b91a8f8af 100644
--- a/src/gui/views/treemodels/placemodel.py
+++ b/src/gui/views/treemodels/placemodel.py
@@ -118,6 +118,16 @@ class PlaceBaseModel(object):
             self.column_handle,
             ]
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.db = None
+        self.gen_cursor = None
+        self.map = None
+        self.fmap = None
+        self.smap = None
+
     def on_get_n_columns(self):
         return len(self.fmap)+1
 
@@ -224,6 +234,13 @@ class PlaceListModel(PlaceBaseModel, FlatBaseModel):
         FlatBaseModel.__init__(self, db, scol, order, tooltip_column=15,
                            search=search, skip=skip, sort_map=sort_map)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        PlaceBaseModel.destroy(self)
+        FlatBaseModel.destroy(self)
+
     def column_name(self, data):
         return unicode(data[2])
 
@@ -246,6 +263,15 @@ class PlaceTreeModel(PlaceBaseModel, TreeBaseModel):
                                 nrgroups = 3,
                                 group_can_have_handle = True)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        PlaceBaseModel.destroy(self)
+        self.hmap = None
+        self.number_items = None
+        TreeBaseModel.destroy(self)
+
     def _set_base_data(self):
         """See TreeBaseModel, for place, most have been set in init of
         PlaceBaseModel
diff --git a/src/gui/views/treemodels/repomodel.py b/src/gui/views/treemodels/repomodel.py
index 5dfda3e32..01508efc1 100644
--- a/src/gui/views/treemodels/repomodel.py
+++ b/src/gui/views/treemodels/repomodel.py
@@ -95,6 +95,18 @@ class RepositoryModel(FlatBaseModel):
         FlatBaseModel.__init__(self, db, scol, order, tooltip_column=14,
                            search=search, skip=skip, sort_map=sort_map)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.db = None
+        self.gen_cursor = None
+        self.get_handles = None
+        self.map = None
+        self.fmap = None
+        self.smap = None
+        FlatBaseModel.destroy(self)
+
     def on_get_n_columns(self):
         return len(self.fmap)+1
 
diff --git a/src/gui/views/treemodels/sourcemodel.py b/src/gui/views/treemodels/sourcemodel.py
index a0bbb7c36..5be3a32ae 100644
--- a/src/gui/views/treemodels/sourcemodel.py
+++ b/src/gui/views/treemodels/sourcemodel.py
@@ -76,6 +76,17 @@ class SourceModel(FlatBaseModel):
         FlatBaseModel.__init__(self,db,scol, order,tooltip_column=7,search=search,
                            skip=skip, sort_map=sort_map)
 
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.db = None
+        self.gen_cursor = None
+        self.map = None
+        self.fmap = None
+        self.smap = None
+        FlatBaseModel.destroy(self)
+
     def on_get_n_columns(self):
         return len(self.fmap)+1
 
diff --git a/src/gui/views/treemodels/treebasemodel.py b/src/gui/views/treemodels/treebasemodel.py
index 801db600c..3d3e24af5 100644
--- a/src/gui/views/treemodels/treebasemodel.py
+++ b/src/gui/views/treemodels/treebasemodel.py
@@ -173,6 +173,12 @@ class NodeMap(object):
     """
     def __init__(self):
         self.id2node = {}
+
+    def destroy(self):
+        """
+        Unset all elements that can prevent garbage collection
+        """
+        self.id2node.clear()
     
     def add_node(self, node):
         """
@@ -310,6 +316,20 @@ class TreeBaseModel(gtk.GenericTreeModel):
         _LOG.debug(self.__class__.__name__ + ' __init__ ' +
                     str(time.clock() - cput) + ' sec')
 
+    def destroy(self):
+        """
+        Unset all elements that prevent garbage collection
+        """
+        self.db = None
+        self.sort_func = None
+        if self.nodemap:
+            self.nodemap.destroy()
+        self.nodemap = None
+        self.rebuild_data = None
+        self._build_data = None
+        self.search = None
+        self.clear_cache()
+
     def _set_base_data(self):
         """
         This method must be overwritten in the inheriting class, setting 
diff --git a/src/gui/widgets/buttons.py b/src/gui/widgets/buttons.py
index 3a3cfccd5..4bcf48d72 100644
--- a/src/gui/widgets/buttons.py
+++ b/src/gui/widgets/buttons.py
@@ -72,6 +72,12 @@ class IconButton(gtk.Button):
             self.connect('button-press-event', func, handle)
             self.connect('key-press-event', func, handle)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        gtk.Button.destroy(self)
+
 #-------------------------------------------------------------------------
 #
 # WarnButton class
@@ -91,6 +97,13 @@ class WarnButton(gtk.Button):
         self.func = None
         self.hide()
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.func = None
+##        gtk.Button.destroy(self)
+
     def on_clicked(self, func):
         self.connect('button-press-event', self._button_press)
         self.func = func
@@ -112,6 +125,12 @@ class SimpleButton(gtk.Button):
         self.add(gtk.image_new_from_stock(image, gtk.ICON_SIZE_BUTTON))
         self.connect('clicked', func)
         self.show()
+
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        gtk.Button.destroy(self)
         
 #-------------------------------------------------------------------------
 #
@@ -127,6 +146,12 @@ class PrivacyButton(object):
         self.set_active(obj.get_privacy())
         self.button.set_sensitive(not readonly)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.obj = None
+
     def set_sensitive(self, val):
         self.button.set_sensitive(val)
 
diff --git a/src/gui/widgets/monitoredwidgets.py b/src/gui/widgets/monitoredwidgets.py
index bb87bf86d..9d670a3f0 100644
--- a/src/gui/widgets/monitoredwidgets.py
+++ b/src/gui/widgets/monitoredwidgets.py
@@ -76,6 +76,14 @@ class MonitoredCheckbox(object):
         self.set_val(obj.get_active())
         if self.on_toggle:
             self.on_toggle(self.get_val())
+
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val = None
+##        self.get_val = None
+##        self.obj = None
         
 #-------------------------------------------------------------------------
 #
@@ -99,6 +107,14 @@ class MonitoredEntry(object):
         if autolist:
             AutoComp.fill_entry(obj, autolist)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val = None
+##        self.get_val = None
+##        self.obj = None
+
     def reinit(self, set_val, get_val):
         self.set_val = set_val
         self.get_val = get_val
@@ -166,6 +182,14 @@ class MonitoredSpinButton(object):
         if autolist:
             AutoComp.fill_entry(obj,autolist)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val = None
+##        self.get_val = None
+##        self.obj = None
+
     def reinit(self, set_val, get_val):
         """
         Reinitialize class with the specified callback functions.
@@ -270,6 +294,14 @@ class MonitoredText(object):
         self.buf.connect('changed', self.on_change)
         obj.set_editable(not read_only)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val = None
+##        self.get_val = None
+##        self.buf = None
+
     def on_change(self, obj):
         s, e = self.buf.get_bounds()
         self.set_val(unicode(self.buf.get_text(s, e, False)))
@@ -301,6 +333,14 @@ class MonitoredType(object):
         self.obj.set_sensitive(not readonly)
         self.obj.connect('changed', self.on_change)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val = None
+##        self.get_val = None
+##        self.obj = None
+
     def reinit(self, set_val, get_val):
         self.set_val = set_val
         self.get_val = get_val
@@ -369,6 +409,14 @@ class MonitoredDataType(object):
         self.obj.set_sensitive(not readonly)
         self.obj.connect('changed', self.on_change)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val = None
+##        self.get_val = None
+##        self.obj = None
+
     def reinit(self, set_val, get_val):
         self.set_val = set_val
         self.get_val = get_val
@@ -410,6 +458,14 @@ class MonitoredMenu(object):
         self.obj.connect('changed', self.on_change)
         self.obj.set_sensitive(not readonly)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val = None
+##        self.get_val = None
+##        self.obj = None
+
     def force(self, value):
         self.obj.set_active(value)
 
@@ -465,6 +521,15 @@ class MonitoredStrMenu(object):
         self.obj.connect('changed', self.on_change)
         self.obj.set_sensitive(not readonly)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val = None
+##        self.get_val = None
+##        self.obj = None
+##        self.model = None
+
     def on_change(self, obj):
         self.set_val(self.data[obj.get_active()])
 
@@ -531,6 +596,15 @@ class MonitoredComboSelectedEntry(object):
         #set correct editable
         self.enable(not read_only)
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.set_val_list = None
+##        self.get_val_list = None
+##        self.objcombo = None
+##        self.objentry = None
+
     def __fill(self):
         """
         Fill combo with data
@@ -643,6 +717,15 @@ class MonitoredTagList(object):
 
         self._display()
 
+##    def destroy(self):
+##        """
+##        Unset all elements that can prevent garbage collection
+##        """
+##        self.uistate = None
+##        self.track = None
+##        self.db = None
+##        self.set_list = None
+
     def _display(self):
         """
         Display the tag list.