diff -r 0ea39719be44 Lib/asyncio/futures.py
--- a/Lib/asyncio/futures.py	Fri Dec 20 10:44:00 2013 +0100
+++ b/Lib/asyncio/futures.py	Fri Dec 20 10:52:48 2013 +0100
@@ -309,6 +309,11 @@ class Future:
         self._schedule_callbacks()
         if _PY34:
             self._log_traceback = True
+            # Clear frames of the traceback to explicitly break a reference
+            # cycle. Frames cannot be cleared immediatly because the current
+            # frame is running.
+            self._loop.call_soon(traceback.clear_frames,
+                                 self._exception.__traceback__)
         else:
             self._tb_logger = _TracebackLogger(exception)
             # Arrange for the logger to be activated after all callbacks