diff --git a/odoo/modules/registry.py b/odoo/modules/registry.py
index 02d1cd6e94a..9294cbbefdf 100644
--- a/odoo/modules/registry.py
+++ b/odoo/modules/registry.py
@@ -151,14 +151,13 @@ class Registry(Mapping):
         """ Delete the registry linked to a given database. """
         with cls._lock:
             if db_name in cls.registries:
-                cls.registries.pop(db_name)
+                del cls.registries[db_name]
 
     @classmethod
     def delete_all(cls):
         """ Delete all the registries. """
         with cls._lock:
-            for db_name in list(cls.registries.keys()):
-                cls.delete(db_name)
+            cls.registries.clear()
 
     #
     # Mapping abstract methods implementation
diff --git a/odoo/service/server.py b/odoo/service/server.py
index cffb6cd4373..0d22862818d 100644
--- a/odoo/service/server.py
+++ b/odoo/service/server.py
@@ -403,7 +403,7 @@ class ThreadedServer(CommonServer):
             time.sleep(SLEEP_INTERVAL + number)     # Steve Reich timing style
             registries = odoo.modules.registry.Registry.registries
             _logger.debug('cron%d polling for jobs', number)
-            for db_name, registry in registries.items():
+            for db_name, registry in registries.d.items():
                 if registry.ready:
                     thread = threading.currentThread()
                     thread.start_time = time.time()
diff --git a/odoo/tools/cache.py b/odoo/tools/cache.py
index 2d50b51aa94..dce88781824 100644
--- a/odoo/tools/cache.py
+++ b/odoo/tools/cache.py
@@ -204,7 +204,7 @@ def log_ormcache_stats(sig=None, frame=None):
     me = threading.currentThread()
     me_dbname = getattr(me, 'dbname', 'n/a')
 
-    for dbname, reg in sorted(Registry.registries.items()):
+    for dbname, reg in sorted(Registry.registries.d.items()):
         # set logger prefix to dbname
         me.dbname = dbname
         entries = defaultdict(int)