tillrohrmann commented on a change in pull request #7320: [FLINK-11171] Avoid concurrent usage of StateSnapshotTransformer URL: https://github.com/apache/flink/pull/7320#discussion_r247968937
########## File path: flink-runtime/src/test/java/org/apache/flink/runtime/state/StateBackendTestBase.java ########## @@ -3902,6 +3906,84 @@ public void testParallelAsyncSnapshots() throws Exception { } } + @Test + public void testNonConcurrentSnapshotTransformerAccess() throws Exception { + Random rnd = new Random(); + BlockerCheckpointStreamFactory streamFactory = new BlockerCheckpointStreamFactory(1024 * 1024); + AbstractKeyedStateBackend<Integer> backend = null; + try { + backend = createKeyedBackend(IntSerializer.INSTANCE); + InternalValueState<Integer, VoidNamespace, String> valueState = backend.createInternalState( + VoidNamespaceSerializer.INSTANCE, + new ValueStateDescriptor<>("test", StringSerializer.INSTANCE), + createSingleThreadAccessCheckingStateSnapshotTransformFactory()); + + valueState.setCurrentNamespace(VoidNamespace.INSTANCE); + + for (int i = 0; i < 100; i++) { + backend.setCurrentKey(i); + valueState.update(StringUtils.getRandomString(rnd,5, 10)); + } + + CheckpointOptions checkpointOptions = CheckpointOptions.forCheckpointWithDefaultLocation(); + + RunnableFuture<SnapshotResult<KeyedStateHandle>> snapshot1 = + backend.snapshot(1L, 0L, streamFactory, checkpointOptions); + + RunnableFuture<SnapshotResult<KeyedStateHandle>> snapshot2 = + backend.snapshot(2L, 0L, streamFactory, checkpointOptions); + + Thread runner1 = new Thread(snapshot1, "snapshot1"); + runner1.start(); + Thread runner2 = new Thread(snapshot2, "snapshot2"); + runner2.start(); + + runner1.join(); + runner2.join(); + + snapshot1.get(); + snapshot2.get(); + } finally { + if (backend != null) { + IOUtils.closeQuietly(backend); + backend.dispose(); + } + } + } + + private static <T> StateSnapshotTransformFactory<T> + createSingleThreadAccessCheckingStateSnapshotTransformFactory() { + return new StateSnapshotTransformFactory<T>() { + @Override + public Optional<StateSnapshotTransformer<T>> createForDeserializedState() { + return createStateSnapshotTransformer(); + } + + @Override + public Optional<StateSnapshotTransformer<byte[]>> createForSerializedState() { + return createStateSnapshotTransformer(); + } + + private <T1> Optional<StateSnapshotTransformer<T1>> createStateSnapshotTransformer() { + return Optional.of(new StateSnapshotTransformer<T1>() { + private Thread currentThread = null; + + @Nullable + @Override + public T1 filterOrTransform(@Nullable T1 value) { + if (currentThread == null) { + currentThread = Thread.currentThread(); + } else { + assertEquals("Concurrent access from another thread", + currentThread, Thread.currentThread()); + } Review comment: The current implementation assumes that there is only a single element to transform, right? Otherwise it should fail with the second element. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services