Apply ugly hotfix to I/O manager

structio/core/kernel.py

@@ -270,6 +270,7 @@ class DefaultKernel(BaseKernel):
             scope.timed_out = True
             error = TimedOut("timed out")
             error.scope = scope
+            scope.cancel()
             self.throw(scope.owner, error)
 
     def wakeup(self):

structio/core/managers/io/simple.py

@@ -73,7 +73,9 @@ class SimpleIOManager(BaseIOManager):
         current_time = kernel.clock.current_time()
         deadline = kernel.get_closest_deadline()
         if deadline == float("inf"):
-            deadline = 0
+            # FIXME: This delay seems to help throttle the calls
+            #   to this method. Should we be calling it this often?
+            deadline = 0.01
         elif deadline > 0:
             deadline -= current_time
         deadline = max(0, deadline)