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Posted to issues@flink.apache.org by GitBox <gi...@apache.org> on 2020/12/01 13:38:44 UTC

[GitHub] [flink] AHeise opened a new pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

AHeise opened a new pull request #14279:
URL: https://github.com/apache/flink/pull/14279


   
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   ## What is the purpose of the change
   
   IteratorSourceReader fails checkpointing when assignment has not yet happened with NPE.
   Furthermore, if the last element of a split has been pulled just before checkpointing, then a split would be created with (to+1, to) leading to an IllegalArgumentException: 'from' must be <= 'to'.
   
   ## Brief change log
   
   - Fixed checkpointing of IteratorSourceReader.
   
   ## Verifying this change
   
   Added ITCase in flink-tests (since we cannot really test checkpointing integration in flink-core).
   
   ## Does this pull request potentially affect one of the following parts:
   
     - Dependencies (does it add or upgrade a dependency): (yes / **no**)
     - The public API, i.e., is any changed class annotated with `@Public(Evolving)`: (yes / **no**)
     - The serializers: (yes / **no** / don't know)
     - The runtime per-record code paths (performance sensitive): (yes / **no** / don't know)
     - Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn/Mesos, ZooKeeper: (yes / **no** / don't know)
     - The S3 file system connector: (yes / **no** / don't know)
   
   ## Documentation
   
     - Does this pull request introduce a new feature? (yes / **no**)
     - If yes, how is the feature documented? (**not applicable** / docs / JavaDocs / not documented)
   


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[GitHub] [flink] AHeise merged pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
AHeise merged pull request #14279:
URL: https://github.com/apache/flink/pull/14279


   


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[GitHub] [flink] flinkbot commented on pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
flinkbot commented on pull request #14279:
URL: https://github.com/apache/flink/pull/14279#issuecomment-736588058


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[GitHub] [flink] AHeise commented on a change in pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
AHeise commented on a change in pull request #14279:
URL: https://github.com/apache/flink/pull/14279#discussion_r533453802



##########
File path: flink-tests/src/test/java/org/apache/flink/api/connector/source/lib/NumberSequenceSourceITCase.java
##########
@@ -0,0 +1,59 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.api.connector.source.lib;
+
+import org.apache.flink.api.common.restartstrategy.RestartStrategies;
+import org.apache.flink.streaming.api.CheckpointingMode;
+import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
+import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
+import org.apache.flink.streaming.util.StreamCollector;
+
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.util.Collection;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.LongStream;
+
+import static org.junit.Assert.assertArrayEquals;
+
+/**
+ * Tests {@link NumberSequenceSource}.
+ */
+public class NumberSequenceSourceITCase {
+	@Rule
+	public StreamCollector collector = new StreamCollector();
+
+	@Test
+	public void testCheckpointingWithDelayedAssignment() throws Exception {
+		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
+		env.setParallelism(1);
+		env.setRestartStrategy(new RestartStrategies.NoRestartStrategyConfiguration());
+		env.enableCheckpointing(50, CheckpointingMode.EXACTLY_ONCE);
+		final SingleOutputStreamOperator<Long> stream = env
+			.fromSequence(0, 100)
+			.map(x -> {
+				Thread.sleep(10);

Review comment:
       Ah, I just noticed that it's much more likely if it's in sync with checkpointing time - so I decreased both to 10 now.




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[GitHub] [flink] AHeise commented on a change in pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
AHeise commented on a change in pull request #14279:
URL: https://github.com/apache/flink/pull/14279#discussion_r533452326



##########
File path: flink-tests/src/test/java/org/apache/flink/api/connector/source/lib/NumberSequenceSourceITCase.java
##########
@@ -0,0 +1,59 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.api.connector.source.lib;
+
+import org.apache.flink.api.common.restartstrategy.RestartStrategies;
+import org.apache.flink.streaming.api.CheckpointingMode;
+import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
+import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
+import org.apache.flink.streaming.util.StreamCollector;
+
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.util.Collection;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.LongStream;
+
+import static org.junit.Assert.assertArrayEquals;
+
+/**
+ * Tests {@link NumberSequenceSource}.
+ */
+public class NumberSequenceSourceITCase {
+	@Rule
+	public StreamCollector collector = new StreamCollector();
+
+	@Test
+	public void testCheckpointingWithDelayedAssignment() throws Exception {
+		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
+		env.setParallelism(1);
+		env.setRestartStrategy(new RestartStrategies.NoRestartStrategyConfiguration());
+		env.enableCheckpointing(50, CheckpointingMode.EXACTLY_ONCE);
+		final SingleOutputStreamOperator<Long> stream = env
+			.fromSequence(0, 100)
+			.map(x -> {
+				Thread.sleep(10);

Review comment:
       Okay, I tested various sleep times and for me 50 showed the issue most reliable (10/10), so I'm going with that.




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[GitHub] [flink] flinkbot commented on pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
flinkbot commented on pull request #14279:
URL: https://github.com/apache/flink/pull/14279#issuecomment-736557866


   Thanks a lot for your contribution to the Apache Flink project. I'm the @flinkbot. I help the community
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   ## Automated Checks
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[GitHub] [flink] flinkbot edited a comment on pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
flinkbot edited a comment on pull request #14279:
URL: https://github.com/apache/flink/pull/14279#issuecomment-736588058


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[GitHub] [flink] AHeise commented on a change in pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
AHeise commented on a change in pull request #14279:
URL: https://github.com/apache/flink/pull/14279#discussion_r533450362



##########
File path: flink-tests/src/test/java/org/apache/flink/api/connector/source/lib/NumberSequenceSourceITCase.java
##########
@@ -0,0 +1,59 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.api.connector.source.lib;
+
+import org.apache.flink.api.common.restartstrategy.RestartStrategies;
+import org.apache.flink.streaming.api.CheckpointingMode;
+import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
+import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
+import org.apache.flink.streaming.util.StreamCollector;
+
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.util.Collection;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.LongStream;
+
+import static org.junit.Assert.assertArrayEquals;
+
+/**
+ * Tests {@link NumberSequenceSource}.
+ */
+public class NumberSequenceSourceITCase {
+	@Rule
+	public StreamCollector collector = new StreamCollector();
+
+	@Test
+	public void testCheckpointingWithDelayedAssignment() throws Exception {
+		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
+		env.setParallelism(1);
+		env.setRestartStrategy(new RestartStrategies.NoRestartStrategyConfiguration());
+		env.enableCheckpointing(50, CheckpointingMode.EXACTLY_ONCE);
+		final SingleOutputStreamOperator<Long> stream = env
+			.fromSequence(0, 100)
+			.map(x -> {
+				Thread.sleep(10);

Review comment:
       Yes, that's what I also thought. However, I also didn't want to make the test too long and was hoping that the sheer amount of AZP executions + VM hiccups actually provide enough coverage.




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[GitHub] [flink] AHeise commented on pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
AHeise commented on pull request #14279:
URL: https://github.com/apache/flink/pull/14279#issuecomment-737733731


   Sure, I haven't found the test in the nick of time. Do you want to merge it or can I do it?


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[GitHub] [flink] flinkbot edited a comment on pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
flinkbot edited a comment on pull request #14279:
URL: https://github.com/apache/flink/pull/14279#issuecomment-736588058


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[GitHub] [flink] flinkbot edited a comment on pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
flinkbot edited a comment on pull request #14279:
URL: https://github.com/apache/flink/pull/14279#issuecomment-736588058


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[GitHub] [flink] StephanEwen commented on pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
StephanEwen commented on pull request #14279:
URL: https://github.com/apache/flink/pull/14279#issuecomment-737203187


   Thanks for fixing this. For simplicity, can we merge this with https://github.com/apache/flink/blob/master/flink-tests/src/test/java/org/apache/flink/api/connector/source/lib/IteratorSourcesITCase.java ?
   
   That is where the tests are so far. Otherwise we have two classes and redundant tests...


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[GitHub] [flink] rkhachatryan commented on a change in pull request #14279: [FLINK-20418][core] Fixing checkpointing of IteratorSourceReader.

Posted by GitBox <gi...@apache.org>.
rkhachatryan commented on a change in pull request #14279:
URL: https://github.com/apache/flink/pull/14279#discussion_r533439656



##########
File path: flink-tests/src/test/java/org/apache/flink/api/connector/source/lib/NumberSequenceSourceITCase.java
##########
@@ -0,0 +1,59 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.flink.api.connector.source.lib;
+
+import org.apache.flink.api.common.restartstrategy.RestartStrategies;
+import org.apache.flink.streaming.api.CheckpointingMode;
+import org.apache.flink.streaming.api.datastream.SingleOutputStreamOperator;
+import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
+import org.apache.flink.streaming.util.StreamCollector;
+
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.util.Collection;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.LongStream;
+
+import static org.junit.Assert.assertArrayEquals;
+
+/**
+ * Tests {@link NumberSequenceSource}.
+ */
+public class NumberSequenceSourceITCase {
+	@Rule
+	public StreamCollector collector = new StreamCollector();
+
+	@Test
+	public void testCheckpointingWithDelayedAssignment() throws Exception {
+		StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
+		env.setParallelism(1);
+		env.setRestartStrategy(new RestartStrategies.NoRestartStrategyConfiguration());
+		env.enableCheckpointing(50, CheckpointingMode.EXACTLY_ONCE);
+		final SingleOutputStreamOperator<Long> stream = env
+			.fromSequence(0, 100)
+			.map(x -> {
+				Thread.sleep(10);

Review comment:
       Sleeping here for a bit longer (50 in my setup) makes the 2nd issue (missing `hasNext`) fail more likely.




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