--- a/cubicweb/server/repository.py	Fri Mar 10 17:03:28 2017 +0100
+++ b/cubicweb/server/repository.py	Fri Mar 10 18:25:35 2017 +0100
@@ -656,11 +656,6 @@
         user._cw = user.cw_rset.req = session
         user.cw_clear_relation_cache()
         self.info('opened session %s for user %s', session, login)
-        with session.new_cnx() as cnx:
-            self.hm.call_hooks('session_open', cnx)
-            # commit connection at this point in case write operation has been
-            # done during `session_open` hooks
-            cnx.commit()
         return session
 
     # session handling ########################################################