[KAFKA-4036] Unsafe dictionary access in VerifiableConsumer service

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Component/s: system tests
• Assignee: Unassigned
• Reporter: Jason Gustafson
• Created: 12/Aug/16 20:51
• Updated: 24/Jan/17 03:09
• Resolved: 24/Jan/17 03:07

Description

Found this in a recent run. Looks like not all changes to the dictionary are guarded with the lock.

test_id:    2016-08-12--001.kafkatest.tests.client.consumer_test.OffsetValidationTest.test_consumer_failure.clean_shutdown=True.enable_autocommit=False
status:     FAIL
run time:   1 minute 32.957 seconds


    dictionary changed size during iteration
Traceback (most recent call last):
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/venv/local/lib/python2.7/site-packages/ducktape/tests/runner.py", line 106, in run_all_tests
    data = self.run_single_test()
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/venv/local/lib/python2.7/site-packages/ducktape/tests/runner.py", line 162, in run_single_test
    return self.current_test_context.function(self.current_test)
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/venv/local/lib/python2.7/site-packages/ducktape/mark/_mark.py", line 331, in wrapper
    return functools.partial(f, *args, **kwargs)(*w_args, **w_kwargs)
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/tests/kafkatest/tests/client/consumer_test.py", line 163, in test_consumer_failure
    self.await_all_members(consumer)
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/tests/kafkatest/tests/verifiable_consumer_test.py", line 83, in await_all_members
    self.await_members(consumer, self.num_consumers)
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/tests/kafkatest/tests/verifiable_consumer_test.py", line 80, in await_members
    err_msg="Consumers failed to join in a reasonable amount of time")
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/venv/local/lib/python2.7/site-packages/ducktape/utils/util.py", line 31, in wait_until
    if condition():
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/tests/kafkatest/tests/verifiable_consumer_test.py", line 78, in <lambda>
    wait_until(lambda: len(consumer.joined_nodes()) == num_consumers,
  File "/var/lib/jenkins/workspace/system-test-kafka-branch-builder/kafka/tests/kafkatest/services/verifiable_consumer.py", line 317, in joined_nodes
    return [handler.node for handler in self.event_handlers.itervalues()
RuntimeError: dictionary changed size during iteration

Issue Links

• duplicates: KAFKA-4673 Python VerifiableConsumer service has thread-safety bug for event_handlers