Myasuka commented on a change in pull request #7813: [FLINK-10712] Support to restore state when using RestartPipelinedRegionStrategy URL: https://github.com/apache/flink/pull/7813#discussion_r275452126
########## File path: flink-tests/src/test/java/org/apache/flink/test/checkpointing/RegionFailoverITCase.java ########## @@ -0,0 +1,392 @@ +/* + * 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.test.checkpointing; + +import org.apache.flink.api.common.functions.MapFunction; +import org.apache.flink.api.common.functions.RichMapFunction; +import org.apache.flink.api.common.restartstrategy.RestartStrategies; +import org.apache.flink.api.common.state.ListState; +import org.apache.flink.api.common.state.ListStateDescriptor; +import org.apache.flink.api.common.state.ValueState; +import org.apache.flink.api.common.state.ValueStateDescriptor; +import org.apache.flink.api.common.typeinfo.TypeInformation; +import org.apache.flink.api.java.functions.KeySelector; +import org.apache.flink.api.java.tuple.Tuple2; +import org.apache.flink.client.program.ClusterClient; +import org.apache.flink.configuration.Configuration; +import org.apache.flink.configuration.JobManagerOptions; +import org.apache.flink.runtime.jobgraph.JobGraph; +import org.apache.flink.runtime.state.CheckpointListener; +import org.apache.flink.runtime.state.FunctionInitializationContext; +import org.apache.flink.runtime.state.FunctionSnapshotContext; +import org.apache.flink.runtime.state.KeyGroupRangeAssignment; +import org.apache.flink.runtime.testutils.MiniClusterResourceConfiguration; +import org.apache.flink.streaming.api.CheckpointingMode; +import org.apache.flink.streaming.api.checkpoint.CheckpointedFunction; +import org.apache.flink.streaming.api.checkpoint.ListCheckpointed; +import org.apache.flink.streaming.api.datastream.DataStreamUtils; +import org.apache.flink.streaming.api.environment.CheckpointConfig; +import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment; +import org.apache.flink.streaming.api.functions.sink.RichSinkFunction; +import org.apache.flink.streaming.api.functions.source.RichParallelSourceFunction; +import org.apache.flink.test.util.MiniClusterWithClientResource; +import org.apache.flink.util.TestLogger; + +import org.apache.commons.collections.CollectionUtils; +import org.junit.AfterClass; +import org.junit.Assert; +import org.junit.Before; +import org.junit.ClassRule; +import org.junit.Test; +import org.junit.rules.TemporaryFolder; + +import java.io.IOException; +import java.util.Collections; +import java.util.HashMap; +import java.util.List; +import java.util.Map; +import java.util.Set; +import java.util.concurrent.atomic.AtomicInteger; +import java.util.concurrent.atomic.AtomicLong; +import java.util.stream.Collectors; +import java.util.stream.IntStream; +import java.util.stream.StreamSupport; + +import static org.junit.Assert.assertEquals; + +/** + * Tests for region failover with multi regions. + */ +public class RegionFailoverITCase extends TestLogger { + + private static final int FAIL_BASE = 1000; + private static final int NUM_OF_REGIONS = 3; + private static final int MAX_PARALLELISM = 2 * NUM_OF_REGIONS; + private static final Set<Integer> EXPECTED_INDICES = IntStream.range(0, NUM_OF_REGIONS).boxed().collect(Collectors.toSet()); + private static final int NUM_OF_RESTARTS = 3; + private static final int NUM_ELEMENTS = FAIL_BASE * 10; + + private static AtomicLong lastCompletedCheckpointId = new AtomicLong(0); + private static AtomicInteger numCompletedCheckpoints = new AtomicInteger(0); + private static AtomicInteger jobFailedCnt = new AtomicInteger(0); + + private static Map<Long, Integer> snapshotIndicesOfSubTask = new HashMap<>(); + + private static MiniClusterWithClientResource cluster; + + private static boolean restoredState = false; + + @ClassRule + public static final TemporaryFolder TEMPORARY_FOLDER = new TemporaryFolder(); + + @Before + public void setup() throws Exception { + Configuration configuration = new Configuration(); + configuration.setString(JobManagerOptions.EXECUTION_FAILOVER_STRATEGY, "region"); + + cluster = new MiniClusterWithClientResource( + new MiniClusterResourceConfiguration.Builder() + .setConfiguration(configuration) + .setNumberTaskManagers(2) + .setNumberSlotsPerTaskManager(2).build()); + cluster.before(); + jobFailedCnt.set(0); + numCompletedCheckpoints.set(0); + } + + @AfterClass + public static void shutDownExistingCluster() { + if (cluster != null) { + cluster.after(); + cluster = null; + } + } + + /** + * Tests that a simple job (Source -> Map) with multi regions could restore with operator state. + * + * <p>The last subtask of Map function in the 1st stream graph would fail {@code NUM_OF_RESTARTS} times, + * and it will verify whether the restored state is identical to last completed checkpoint's. + */ + @Test(timeout = 60000) + public void testMultiRegionFailover() { + try { + JobGraph jobGraph = createJobGraph(); + ClusterClient<?> client = cluster.getClusterClient(); + client.submitJob(jobGraph, RegionFailoverITCase.class.getClassLoader()); + verifyAfterJobExecuted(); + } + catch (Exception e) { + e.printStackTrace(); + Assert.fail(e.getMessage()); + } + } + + private void verifyAfterJobExecuted() { + Assert.assertTrue("The test multi-region job has never ever restored state.", restoredState); + + for (Map<Integer, Integer> map : ValidatingSink.maps) { + for (Map.Entry<Integer, Integer> entry : map.entrySet()) { + assertEquals(Math.min(2 * entry.getKey() + 1, NUM_ELEMENTS), (int) entry.getValue()); + } + } + } + + private JobGraph createJobGraph() { + + StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment(); + env.setParallelism(NUM_OF_REGIONS); + env.setMaxParallelism(MAX_PARALLELISM); + env.enableCheckpointing(200, CheckpointingMode.EXACTLY_ONCE); + env.getCheckpointConfig().enableExternalizedCheckpoints(CheckpointConfig.ExternalizedCheckpointCleanup.RETAIN_ON_CANCELLATION); + env.disableOperatorChaining(); + env.getConfig().setRestartStrategy(RestartStrategies.fixedDelayRestart(NUM_OF_RESTARTS, 0L)); + env.getConfig().disableSysoutLogging(); + + // Use DataStreamUtils#reinterpretAsKeyed to avoid merge regions and this stream graph would exist num of 'NUM_OF_REGIONS' individual regions. + DataStreamUtils.reinterpretAsKeyedStream( + env.addSource(new StringGeneratingSourceFunction(NUM_ELEMENTS, NUM_ELEMENTS / NUM_OF_RESTARTS)) + .setParallelism(NUM_OF_REGIONS), + (KeySelector<Tuple2<Integer, Integer>, Integer>) value -> value.f0, + TypeInformation.of(Integer.class)) + .map(new FailingMapperFunction(NUM_OF_RESTARTS)) + .setParallelism(NUM_OF_REGIONS) + .addSink(new ValidatingSink()) + .setParallelism(NUM_OF_REGIONS); + + // another stream graph totally disconnected with the above one. + env.addSource(new StringGeneratingSourceFunction(NUM_ELEMENTS, NUM_ELEMENTS / NUM_OF_RESTARTS)).setParallelism(1) + .map((MapFunction<Tuple2<Integer, Integer>, Object>) value -> value).setParallelism(1); + + return env.getStreamGraph().getJobGraph(); + } + + private static class StringGeneratingSourceFunction extends RichParallelSourceFunction<Tuple2<Integer, Integer>> + implements CheckpointListener, CheckpointedFunction { + private static final long serialVersionUID = 1L; + + private final long numElements; + private final long checkpointLatestAt; + + private int index = -1; + + private int lastRegionIndex = -1; + + private volatile boolean isRunning = true; + + private ListState<Integer> listState; + + private static final ListStateDescriptor<Integer> stateDescriptor = new ListStateDescriptor<>("list-1", Integer.class); + + private ListState<Integer> unionListState; + + private static final ListStateDescriptor<Integer> unionStateDescriptor = new ListStateDescriptor<>("list-2", Integer.class); + + StringGeneratingSourceFunction(long numElements, long checkpointLatestAt) { + this.numElements = numElements; + this.checkpointLatestAt = checkpointLatestAt; + } + + @Override + public void run(SourceContext<Tuple2<Integer, Integer>> ctx) throws Exception { + if (index < 0) { + // not been restored, so initialize + index = 0; + } + + int subTaskIndex = getRuntimeContext().getIndexOfThisSubtask(); + while (isRunning && index < numElements) { + + synchronized (ctx.getCheckpointLock()) { + index += 1; + int key = index / 2; + int forwardTaskIndex = KeyGroupRangeAssignment.assignKeyToParallelOperator(key, MAX_PARALLELISM, NUM_OF_REGIONS); + // pre-partition output keys + if (forwardTaskIndex == subTaskIndex) { + // we would send data with the same key twice. + ctx.collect(Tuple2.of(key, index)); + } + } + + if (numCompletedCheckpoints.get() < 3) { + // not yet completed enough checkpoints, so slow down + if (index < checkpointLatestAt) { + // mild slow down + Thread.sleep(1); + } else { + // wait until the checkpoints are completed + while (isRunning && numCompletedCheckpoints.get() < 3) { + Thread.sleep(300); + } + } + } + if (jobFailedCnt.get() < NUM_OF_RESTARTS) { + // slow down if job has not failed for 'NUM_OF_RESTARTS' times. + Thread.sleep(1); + } + } + } + + @Override + public void cancel() { + isRunning = false; + } + + @Override + public void notifyCheckpointComplete(long checkpointId) { + if (getRuntimeContext().getIndexOfThisSubtask() == NUM_OF_REGIONS - 1) { + lastCompletedCheckpointId.set(checkpointId); + snapshotIndicesOfSubTask.put(checkpointId, lastRegionIndex); + numCompletedCheckpoints.incrementAndGet(); + } + } + + @Override + public void snapshotState(FunctionSnapshotContext context) throws Exception { + int indexOfThisSubtask = getRuntimeContext().getIndexOfThisSubtask(); + if (indexOfThisSubtask != 0) { + listState.clear(); + listState.add(index); + if (indexOfThisSubtask == NUM_OF_REGIONS - 1) { + lastRegionIndex = index; + } + } + unionListState.clear(); + unionListState.add(indexOfThisSubtask); + } + + @Override + public void initializeState(FunctionInitializationContext context) throws Exception { + int indexOfThisSubtask = getRuntimeContext().getIndexOfThisSubtask(); + if (context.isRestored()) { + restoredState = true; + + unionListState = context.getOperatorStateStore().getUnionListState(unionStateDescriptor); + Set<Integer> actualIndices = StreamSupport.stream(unionListState.get().spliterator(), false).collect(Collectors.toSet()); + Assert.assertTrue(CollectionUtils.isEqualCollection(EXPECTED_INDICES, actualIndices)); + + if (indexOfThisSubtask == 0) { + listState = context.getOperatorStateStore().getListState(stateDescriptor); + Assert.assertTrue("list state should be empty for subtask-0", + ((List<Integer>) listState.get()).isEmpty()); + } else { + listState = context.getOperatorStateStore().getListState(stateDescriptor); + Assert.assertTrue("list state should not be empty for subtask-" + indexOfThisSubtask, + ((List<Integer>) listState.get()).size() > 0); + + if (indexOfThisSubtask == NUM_OF_REGIONS - 1) { + index = listState.get().iterator().next(); + if (index != snapshotIndicesOfSubTask.get(lastCompletedCheckpointId.get())) { + throw new RuntimeException("Test failed due to unexpected recovered index: " + index + + ", while last completed checkpoint record index: " + snapshotIndicesOfSubTask.get(lastCompletedCheckpointId.get())); + } + } + } + } else { + unionListState = context.getOperatorStateStore().getUnionListState(unionStateDescriptor); + + if (indexOfThisSubtask != 0) { + listState = context.getOperatorStateStore().getListState(stateDescriptor); + } + } + + } + } + + private static class FailingMapperFunction extends RichMapFunction<Tuple2<Integer, Integer>, Tuple2<Integer, Integer>> { + private final int restartTimes; + private ValueState<Integer> valueState; Review comment: I'll send value as tuple of `<index/2, index>` from `StringGeneratingSourceFunction`, e.g. `1, 2` and `1, 3` would be emitted. `FailingMapperFunction` would then store keyed state `valueState` which tracks the maximum of value for the corresponding key, and emit `<key, max-value>` to `ValidatingSink`. In other words, we would have `1,3` finally in `ValidatingSink`'s `maps`. In `verifyAfterJobExecuted()` method, I'll then verify the `maps` in `ValidatingSink` works as expected to validate if key state has ever properly restored. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to 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
