[2.7] bpo-30414: multiprocessing.Queue._feed do not break from main loop on exc (GH-1683) (#1817)
* bpo-30414: multiprocesing.Queue._feed do not break from main loop on exc
Queue background running thread was not handling exceptions correctly.
Any exception occurred inside thread (putting unpickable object) cause
feeder to finish running. After that every message put into queue is
silently ignored.
* bpo-30414: multiprocesing.Queue._feed do not break from main loop on exc
Queue background running thread was not handling exceptions correctly.
Any exception occurred inside thread (putting unpickable object) cause
feeder to finish running. After that every message put into queue is
silently ignored..
(cherry picked from commit bc50f03db4f58c869b78e98468e374d7e61f1227)
diff --git a/Lib/multiprocessing/queues.py b/Lib/multiprocessing/queues.py
index a88e298..bb1e728 100644
--- a/Lib/multiprocessing/queues.py
+++ b/Lib/multiprocessing/queues.py
@@ -244,8 +244,8 @@
else:
wacquire = None
- try:
- while 1:
+ while 1:
+ try:
nacquire()
try:
if not buffer:
@@ -270,19 +270,17 @@
wrelease()
except IndexError:
pass
- except Exception, e:
- # Since this runs in a daemon thread the resources it uses
- # may be become unusable while the process is cleaning up.
- # We ignore errors which happen after the process has
- # started to cleanup.
- try:
+ except Exception as e:
+ # Since this runs in a daemon thread the resources it uses
+ # may be become unusable while the process is cleaning up.
+ # We ignore errors which happen after the process has
+ # started to cleanup.
if is_exiting():
info('error in queue thread: %s', e)
+ return
else:
import traceback
traceback.print_exc()
- except Exception:
- pass
_sentinel = object()
diff --git a/Lib/test/test_multiprocessing.py b/Lib/test/test_multiprocessing.py
index 4d39501..8a6bb78 100644
--- a/Lib/test/test_multiprocessing.py
+++ b/Lib/test/test_multiprocessing.py
@@ -641,6 +641,21 @@
self.fail("Probable regression on import lock contention;"
" see Issue #22853")
+ def test_queue_feeder_donot_stop_onexc(self):
+ # bpo-30414: verify feeder handles exceptions correctly
+ if self.TYPE != 'processes':
+ self.skipTest('test not appropriate for {}'.format(self.TYPE))
+
+ class NotSerializable(object):
+ def __reduce__(self):
+ raise AttributeError
+ with test.support.captured_stderr():
+ q = self.Queue()
+ q.put(NotSerializable())
+ q.put(True)
+ self.assertTrue(q.get(timeout=0.1))
+
+
#
#
#
diff --git a/Misc/NEWS b/Misc/NEWS
index 3c6f829..ba5d5d1 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -49,6 +49,9 @@
Library
-------
+- bpo-30414: multiprocessing.Queue._feed background running
+ thread do not break from main loop on exception.
+
- bpo-30003: Fix handling escape characters in HZ codec. Based on patch
by Ma Lin.