- Mapped state internals have been reworked to allow for a 50% reduction

in callcounts specific to the "expiration" of objects, as in
the "auto expire" feature of :meth:`.Session.commit` and
for :meth:`.Session.expire_all`, as well as in the "cleanup" step
which occurs when object states are garbage collected.
fixes #3307

1 files changed, 8 insertions, 1 deletions

diff --git a/lib/sqlalchemy/orm/identity.py b/lib/sqlalchemy/orm/identity.py
index 24dd47859..769010950 100644
--- a/lib/sqlalchemy/orm/identity.py
+++ b/lib/sqlalchemy/orm/identity.py
@@ -44,7 +44,8 @@ class IdentityMap(object):
 
     def _manage_removed_state(self, state):
         del state._instance_dict
-        self._modified.discard(state)
+        if state.modified:
+            self._modified.discard(state)
 
     def _dirty_states(self):
         return self._modified
@@ -186,6 +187,9 @@ class WeakInstanceDict(IdentityMap):
         else:
             return list(self._dict.values())
 
+    def _fast_discard(self, state):
+        self._dict.pop(state.key, None)
+
     def discard(self, state):
         st = self._dict.pop(state.key, None)
         if st:
@@ -264,6 +268,9 @@ class StrongInstanceDict(IdentityMap):
         self._dict[key] = state.obj()
         state._instance_dict = self._wr
 
+    def _fast_discard(self, state):
+        self._dict.pop(state.key, None)
+
     def discard(self, state):
         obj = self._dict.pop(state.key, None)
         if obj is not None: