Issue #10332: multiprocessing: fix a race condition when a Pool is closed
before all tasks have completed.
diff --git a/Lib/test/test_multiprocessing.py b/Lib/test/test_multiprocessing.py
index 201fa98..14847d9 100644
--- a/Lib/test/test_multiprocessing.py
+++ b/Lib/test/test_multiprocessing.py
@@ -1168,6 +1168,20 @@
p.close()
p.join()
+ def test_pool_worker_lifetime_early_close(self):
+ # Issue #10332: closing a pool whose workers have limited lifetimes
+ # before all the tasks completed would make join() hang.
+ p = multiprocessing.Pool(3, maxtasksperchild=1)
+ results = []
+ for i in range(6):
+ results.append(p.apply_async(sqr, (i, 0.3)))
+ p.close()
+ p.join()
+ # check the results
+ for (j, res) in enumerate(results):
+ self.assertEqual(res.get(), sqr(j))
+
+
#
# Test that manager has expected number of shared objects left
#