Memoize package selection results in the depgraph for better performance.

svn path=/main/trunk/; revision=9715

diff --git a/pym/_emerge/__init__.py b/pym/_emerge/__init__.py
index a4361e10942e2f7f84b73c1188b3b8337f729f12..1485f932c953eac8f604af7a15eaa30c13416d8e 100644 (file)
--- a/pym/_emerge/__init__.py
+++ b/pym/_emerge/__init__.py
@@ -1588,6 +1588,8 @@ class depgraph(object):
                self._required_set_names = set(["system", "world"])
                self._select_atoms = self._select_atoms_highest_available
                self._select_package = self._select_pkg_highest_available
+               self._highest_pkg_cache = {}
+               self._installed_pkg_cache = {}
 
        def _show_slot_collision_notice(self):
                """Show an informational message advising the user to mask one of the
@@ -2479,6 +2481,15 @@ class depgraph(object):
                print
 
        def _select_pkg_highest_available(self, root, atom, onlydeps=False):
+               cache_key = (root, atom, onlydeps)
+               ret = self._highest_pkg_cache.get(cache_key)
+               if ret is not None:
+                       return ret
+               ret = self._select_pkg_highest_available_imp(root, atom, onlydeps=onlydeps)
+               self._highest_pkg_cache[cache_key] = ret
+               return ret
+
+       def _select_pkg_highest_available_imp(self, root, atom, onlydeps=False):
                pkgsettings = self.pkgsettings[root]
                dbs = self._filtered_trees[root]["dbs"]
                vardb = self.roots[root].trees["vartree"].dbapi
@@ -2712,12 +2723,18 @@ class depgraph(object):
                e_pkg = self._slot_pkg_map[root].get(slot_atom)
                if e_pkg:
                        return e_pkg, e_pkg
+               cache_key = (root, atom, onlydeps)
+               ret = self._installed_pkg_cache.get(cache_key)
+               if ret is not None:
+                       return ret
                metadata = dict(izip(self._mydbapi_keys,
                        graph_db.aux_get(cpv, self._mydbapi_keys)))
                pkg = Package(cpv=cpv, built=True,
                        installed=True, type_name="installed",
                        metadata=metadata, root=root)
-               return pkg, None
+               ret = pkg, None
+               self._installed_pkg_cache[cache_key] = ret
+               return ret
 
        def _complete_graph(self):
                """