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Posted to commits@flink.apache.org by dw...@apache.org on 2021/02/22 10:45:19 UTC
[flink] 01/03: [FLINK-21206] Implement HeapKeyValueStateIterator
This is an automated email from the ASF dual-hosted git repository.
dwysakowicz pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/flink.git
commit 5010d2ae8f77f20304411b34b7893518da9cdf66
Author: Dawid Wysakowicz <dw...@apache.org>
AuthorDate: Mon Jan 25 09:05:49 2021 +0100
[FLINK-21206] Implement HeapKeyValueStateIterator
---
.../flink/runtime/state/KeyValueStateIterator.java | 4 +-
.../state/heap/HeapKeyValueStateIterator.java | 421 +++++++++++++++++++++
.../state/SavepointStateBackendSwitchTestBase.java | 65 ++--
3 files changed, 467 insertions(+), 23 deletions(-)
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/state/KeyValueStateIterator.java b/flink-runtime/src/main/java/org/apache/flink/runtime/state/KeyValueStateIterator.java
index 28a3266..cf9cf16 100644
--- a/flink-runtime/src/main/java/org/apache/flink/runtime/state/KeyValueStateIterator.java
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/state/KeyValueStateIterator.java
@@ -18,6 +18,8 @@
package org.apache.flink.runtime.state;
+import java.io.IOException;
+
/**
* Iterator that over all key-value state entries in a {@link KeyedStateBackend}. For use during
* snapshotting.
@@ -31,7 +33,7 @@ public interface KeyValueStateIterator extends AutoCloseable {
* Advances the iterator. Should only be called if {@link #isValid()} returned true. Valid flag
* can only change after calling {@link #next()}.
*/
- void next();
+ void next() throws IOException;
/** Returns the key-group for the current key. */
int keyGroup();
diff --git a/flink-runtime/src/main/java/org/apache/flink/runtime/state/heap/HeapKeyValueStateIterator.java b/flink-runtime/src/main/java/org/apache/flink/runtime/state/heap/HeapKeyValueStateIterator.java
new file mode 100644
index 0000000..3f37640
--- /dev/null
+++ b/flink-runtime/src/main/java/org/apache/flink/runtime/state/heap/HeapKeyValueStateIterator.java
@@ -0,0 +1,421 @@
+/*
+ * 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.runtime.state.heap;
+
+import org.apache.flink.annotation.Internal;
+import org.apache.flink.api.common.typeutils.TypeSerializer;
+import org.apache.flink.api.common.typeutils.base.ListSerializer;
+import org.apache.flink.api.common.typeutils.base.MapSerializer;
+import org.apache.flink.core.memory.DataOutputSerializer;
+import org.apache.flink.runtime.state.CompositeKeySerializationUtils;
+import org.apache.flink.runtime.state.IterableStateSnapshot;
+import org.apache.flink.runtime.state.KeyGroupRange;
+import org.apache.flink.runtime.state.KeyValueStateIterator;
+import org.apache.flink.runtime.state.ListDelimitedSerializer;
+import org.apache.flink.runtime.state.RegisteredKeyValueStateBackendMetaInfo;
+import org.apache.flink.runtime.state.RegisteredPriorityQueueStateBackendMetaInfo;
+import org.apache.flink.runtime.state.SerializedCompositeKeyBuilder;
+import org.apache.flink.runtime.state.StateEntry;
+import org.apache.flink.runtime.state.StateSnapshot;
+
+import javax.annotation.Nonnegative;
+import javax.annotation.Nonnull;
+import javax.annotation.concurrent.NotThreadSafe;
+
+import java.io.IOException;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+
+import static org.apache.flink.util.Preconditions.checkNotNull;
+
+/**
+ * A {@link org.apache.flink.runtime.state.KeyValueStateIterator} over Heap backend snapshot
+ * resources.
+ */
+@Internal
+@NotThreadSafe
+public final class HeapKeyValueStateIterator implements KeyValueStateIterator {
+
+ private static final byte[] EMPTY_BYTE_ARRAY = new byte[0];
+
+ private final Map<StateUID, Integer> stateNamesToId;
+ private final Map<StateUID, StateSnapshot> stateStableSnapshots;
+ private final int keyGroupPrefixBytes;
+
+ private boolean isValid;
+ private boolean newKeyGroup;
+ private boolean newKVState;
+ private byte[] currentKey;
+ private byte[] currentValue;
+
+ /** Iterator over the key groups of the corresponding key group range. */
+ private final Iterator<Integer> keyGroupIterator;
+ /** The current value of the keyGroupIterator. */
+ private int currentKeyGroup;
+
+ /** Iterator over all states present in the snapshots. */
+ private Iterator<StateUID> statesIterator;
+ /** The current value of the statesIterator. */
+ private StateUID currentState;
+ /**
+ * An iterator over the values of the current state. It can be one of three:
+ *
+ * <ul>
+ * <li>{@link QueueIterator} for iterating over entries in a priority queue
+ * <li>{@link StateTableIterator} for iterating over entries in a StateTable
+ * <li>{@link MapStateIterator} for iterating over entries in a user map, this one falls back
+ * to the upper one automatically if exhausted
+ * </ul>
+ */
+ private SingleStateIterator currentStateIterator;
+ /** Helpers for serializing state into the unified format. */
+ private final DataOutputSerializer valueOut = new DataOutputSerializer(64);
+
+ private final ListDelimitedSerializer listDelimitedSerializer = new ListDelimitedSerializer();
+ private final SerializedCompositeKeyBuilder<Object> compositeKeyBuilder;
+
+ public HeapKeyValueStateIterator(
+ @Nonnull final KeyGroupRange keyGroupRange,
+ @Nonnull final TypeSerializer<?> keySerializer,
+ @Nonnegative final int totalKeyGroups,
+ @Nonnull final Map<StateUID, Integer> stateNamesToId,
+ @Nonnull final Map<StateUID, StateSnapshot> stateSnapshots)
+ throws IOException {
+ checkNotNull(keyGroupRange);
+ checkNotNull(keySerializer);
+ this.stateNamesToId = checkNotNull(stateNamesToId);
+ this.stateStableSnapshots = checkNotNull(stateSnapshots);
+
+ this.statesIterator = stateSnapshots.keySet().iterator();
+ this.keyGroupIterator = keyGroupRange.iterator();
+
+ this.keyGroupPrefixBytes =
+ CompositeKeySerializationUtils.computeRequiredBytesInKeyGroupPrefix(totalKeyGroups);
+ this.compositeKeyBuilder =
+ new SerializedCompositeKeyBuilder<>(
+ castToType(keySerializer), keyGroupPrefixBytes, 32);
+
+ if (!keyGroupIterator.hasNext() || !statesIterator.hasNext()) {
+ // stop early, no key groups or states
+ isValid = false;
+ } else {
+ currentKeyGroup = keyGroupIterator.next();
+ next();
+ this.newKeyGroup = true;
+ }
+ }
+
+ @Override
+ public boolean isValid() {
+ return isValid;
+ }
+
+ @Override
+ public boolean isNewKeyValueState() {
+ return this.newKVState;
+ }
+
+ @Override
+ public boolean isNewKeyGroup() {
+ return this.newKeyGroup;
+ }
+
+ @Override
+ public int keyGroup() {
+ return currentKeyGroup;
+ }
+
+ @Override
+ public int kvStateId() {
+ return stateNamesToId.get(currentState);
+ }
+
+ @Override
+ public void next() throws IOException {
+ this.newKVState = false;
+ this.newKeyGroup = false;
+
+ boolean nextElementSet = false;
+ do {
+ if (currentState == null) {
+ boolean hasNextState = moveToNextState();
+ if (!hasNextState) {
+ isValid = false;
+ return;
+ }
+ }
+
+ boolean hasStateEntry = currentStateIterator != null && currentStateIterator.hasNext();
+ if (!hasStateEntry) {
+ this.currentState = null;
+ }
+
+ if (hasStateEntry) {
+ nextElementSet = currentStateIterator.writeOutNext();
+ }
+ } while (!nextElementSet);
+ isValid = true;
+ }
+
+ private boolean moveToNextState() throws IOException {
+ if (statesIterator.hasNext()) {
+ this.currentState = statesIterator.next();
+ this.newKVState = true;
+ } else if (keyGroupIterator.hasNext()) {
+ this.currentKeyGroup = keyGroupIterator.next();
+ resetStates();
+ this.newKeyGroup = true;
+ this.newKVState = true;
+ } else {
+ return false;
+ }
+
+ StateSnapshot stateSnapshot = this.stateStableSnapshots.get(currentState);
+ setCurrentStateIterator(stateSnapshot);
+
+ // set to a valid entry
+ return true;
+ }
+
+ private void resetStates() {
+ this.statesIterator = stateStableSnapshots.keySet().iterator();
+ this.currentState = statesIterator.next();
+ }
+
+ @SuppressWarnings("unchecked")
+ private void setCurrentStateIterator(StateSnapshot stateSnapshot) throws IOException {
+ if (stateSnapshot instanceof IterableStateSnapshot) {
+ RegisteredKeyValueStateBackendMetaInfo<Object, Object> metaInfo =
+ new RegisteredKeyValueStateBackendMetaInfo<>(
+ stateSnapshot.getMetaInfoSnapshot());
+ Iterator<? extends StateEntry<?, ?, ?>> snapshotIterator =
+ ((IterableStateSnapshot<?, ?, ?>) stateSnapshot).getIterator(currentKeyGroup);
+ this.currentStateIterator = new StateTableIterator(snapshotIterator, metaInfo);
+ } else if (stateSnapshot instanceof HeapPriorityQueueStateSnapshot) {
+ Iterator<Object> snapshotIterator =
+ ((HeapPriorityQueueStateSnapshot<Object>) stateSnapshot)
+ .getIteratorForKeyGroup(currentKeyGroup);
+ RegisteredPriorityQueueStateBackendMetaInfo<Object> metaInfo =
+ new RegisteredPriorityQueueStateBackendMetaInfo<>(
+ stateSnapshot.getMetaInfoSnapshot());
+ this.currentStateIterator = new QueueIterator<>(snapshotIterator, metaInfo);
+ } else {
+ throw new IllegalStateException("Unknown snapshot type: " + stateSnapshot);
+ }
+ }
+
+ /** A common interface for writing out a single entry in a state. */
+ private interface SingleStateIterator {
+
+ boolean hasNext();
+
+ /**
+ * Sets the {@link #currentKey} and {@link #currentValue} to the value of the next entry in
+ * the state.
+ *
+ * @return false if an entry was empty. It can be the case if we try to serialize an empty
+ * Map or List. In that case we should skip to a next entry.
+ */
+ boolean writeOutNext() throws IOException;
+ }
+
+ private final class StateTableIterator implements SingleStateIterator {
+
+ private final Iterator<? extends StateEntry<?, ?, ?>> entriesIterator;
+ private final RegisteredKeyValueStateBackendMetaInfo<?, ?> stateSnapshot;
+
+ private StateTableIterator(
+ Iterator<? extends StateEntry<?, ?, ?>> entriesIterator,
+ RegisteredKeyValueStateBackendMetaInfo<?, ?> stateSnapshot) {
+ this.entriesIterator = entriesIterator;
+ this.stateSnapshot = stateSnapshot;
+ }
+
+ @Override
+ public boolean hasNext() {
+ return entriesIterator.hasNext();
+ }
+
+ @Override
+ public boolean writeOutNext() throws IOException {
+ StateEntry<?, ?, ?> currentEntry = entriesIterator.next();
+ valueOut.clear();
+ compositeKeyBuilder.setKeyAndKeyGroup(currentEntry.getKey(), keyGroup());
+ compositeKeyBuilder.setNamespace(
+ currentEntry.getNamespace(),
+ castToType(stateSnapshot.getNamespaceSerializer()));
+ TypeSerializer<?> stateSerializer = stateSnapshot.getStateSerializer();
+ switch (stateSnapshot.getStateType()) {
+ case AGGREGATING:
+ case REDUCING:
+ case FOLDING:
+ case VALUE:
+ return writeOutValue(currentEntry, stateSerializer);
+ case LIST:
+ return writeOutList(currentEntry, stateSerializer);
+ case MAP:
+ return writeOutMap(currentEntry, stateSerializer);
+ default:
+ throw new IllegalStateException("");
+ }
+ }
+
+ private boolean writeOutValue(
+ StateEntry<?, ?, ?> currentEntry, TypeSerializer<?> stateSerializer)
+ throws IOException {
+ currentKey = compositeKeyBuilder.build();
+ castToType(stateSerializer).serialize(currentEntry.getState(), valueOut);
+ currentValue = valueOut.getCopyOfBuffer();
+ return true;
+ }
+
+ @SuppressWarnings("unchecked")
+ private boolean writeOutList(
+ StateEntry<?, ?, ?> currentEntry, TypeSerializer<?> stateSerializer)
+ throws IOException {
+ List<Object> state = (List<Object>) currentEntry.getState();
+ if (state.isEmpty()) {
+ return false;
+ }
+ ListSerializer<Object> listSerializer = (ListSerializer<Object>) stateSerializer;
+ currentKey = compositeKeyBuilder.build();
+ currentValue =
+ listDelimitedSerializer.serializeList(
+ state, listSerializer.getElementSerializer());
+ return true;
+ }
+
+ @SuppressWarnings("unchecked")
+ private boolean writeOutMap(
+ StateEntry<?, ?, ?> currentEntry, TypeSerializer<?> stateSerializer)
+ throws IOException {
+ Map<Object, Object> state = (Map<Object, Object>) currentEntry.getState();
+ if (state.isEmpty()) {
+ return false;
+ }
+ MapSerializer<Object, Object> mapSerializer =
+ (MapSerializer<Object, Object>) stateSerializer;
+ currentStateIterator =
+ new MapStateIterator(
+ state,
+ mapSerializer.getKeySerializer(),
+ mapSerializer.getValueSerializer(),
+ this);
+ return currentStateIterator.writeOutNext();
+ }
+ }
+
+ private final class MapStateIterator implements SingleStateIterator {
+
+ private final Iterator<Map.Entry<Object, Object>> mapEntries;
+ private final TypeSerializer<Object> userKeySerializer;
+ private final TypeSerializer<Object> userValueSerializer;
+ private final StateTableIterator parentIterator;
+
+ private MapStateIterator(
+ Map<Object, Object> mapEntries,
+ TypeSerializer<Object> userKeySerializer,
+ TypeSerializer<Object> userValueSerializer,
+ StateTableIterator parentIterator) {
+ assert !mapEntries.isEmpty();
+ this.mapEntries = mapEntries.entrySet().iterator();
+ this.userKeySerializer = userKeySerializer;
+ this.userValueSerializer = userValueSerializer;
+ this.parentIterator = parentIterator;
+ }
+
+ @Override
+ public boolean hasNext() {
+ // we should never end up here with an exhausted map iterator
+ // if an iterator is exhausted in the writeOutNext we switch back to
+ // the originating StateTableIterator
+ assert mapEntries.hasNext();
+ return true;
+ }
+
+ @Override
+ public boolean writeOutNext() throws IOException {
+ Map.Entry<Object, Object> entry = mapEntries.next();
+ valueOut.clear();
+ currentKey =
+ compositeKeyBuilder.buildCompositeKeyUserKey(entry.getKey(), userKeySerializer);
+ Object userValue = entry.getValue();
+ valueOut.writeBoolean(userValue == null);
+ userValueSerializer.serialize(userValue, valueOut);
+ currentValue = valueOut.getCopyOfBuffer();
+
+ if (!mapEntries.hasNext()) {
+ currentStateIterator = parentIterator;
+ }
+ return true;
+ }
+ }
+
+ private final class QueueIterator<T> implements SingleStateIterator {
+ private final Iterator<T> elementsForKeyGroup;
+ private final RegisteredPriorityQueueStateBackendMetaInfo<T> metaInfo;
+ private final DataOutputSerializer keyOut = new DataOutputSerializer(128);
+ private final int afterKeyMark;
+
+ public QueueIterator(
+ Iterator<T> elementsForKeyGroup,
+ RegisteredPriorityQueueStateBackendMetaInfo<T> metaInfo)
+ throws IOException {
+ this.elementsForKeyGroup = elementsForKeyGroup;
+ this.metaInfo = metaInfo;
+ CompositeKeySerializationUtils.writeKeyGroup(keyGroup(), keyGroupPrefixBytes, keyOut);
+ afterKeyMark = keyOut.length();
+ }
+
+ @Override
+ public boolean hasNext() {
+ return elementsForKeyGroup.hasNext();
+ }
+
+ @Override
+ public boolean writeOutNext() throws IOException {
+ currentValue = EMPTY_BYTE_ARRAY;
+ keyOut.setPosition(afterKeyMark);
+ T next = elementsForKeyGroup.next();
+ metaInfo.getElementSerializer().serialize(next, keyOut);
+ currentKey = keyOut.getCopyOfBuffer();
+ return true;
+ }
+ }
+
+ @SuppressWarnings("unchecked")
+ @Nonnull
+ private static <T> TypeSerializer<T> castToType(@Nonnull TypeSerializer<?> serializer) {
+ return (TypeSerializer<T>) serializer;
+ }
+
+ @Override
+ public byte[] key() {
+ return currentKey;
+ }
+
+ @Override
+ public byte[] value() {
+ return currentValue;
+ }
+
+ @Override
+ public void close() {}
+}
diff --git a/flink-tests/src/test/java/org/apache/flink/test/state/SavepointStateBackendSwitchTestBase.java b/flink-tests/src/test/java/org/apache/flink/test/state/SavepointStateBackendSwitchTestBase.java
index 933b8df..d54b667 100644
--- a/flink-tests/src/test/java/org/apache/flink/test/state/SavepointStateBackendSwitchTestBase.java
+++ b/flink-tests/src/test/java/org/apache/flink/test/state/SavepointStateBackendSwitchTestBase.java
@@ -56,6 +56,7 @@ import java.util.Map;
import java.util.concurrent.RunnableFuture;
import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.Matchers.contains;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertThat;
@@ -101,6 +102,7 @@ public abstract class SavepointStateBackendSwitchTestBase {
final Integer namespace1 = 1;
final Integer namespace2 = 2;
final Integer namespace3 = 3;
+ final Integer namespace4 = 4;
try (final CheckpointableKeyedStateBackend<String> keyedBackend =
fromBackend.createBackend(
@@ -113,7 +115,8 @@ public abstract class SavepointStateBackendSwitchTestBase {
listStateDescriptor,
namespace1,
namespace2,
- namespace3);
+ namespace3,
+ namespace4);
}
final SnapshotResult<KeyedStateHandle> stateHandles;
@@ -136,6 +139,7 @@ public abstract class SavepointStateBackendSwitchTestBase {
namespace1,
namespace2,
namespace3,
+ namespace4,
keyedBackend);
}
}
@@ -159,7 +163,8 @@ public abstract class SavepointStateBackendSwitchTestBase {
ListStateDescriptor<Long> listStateDescriptor,
Integer namespace1,
Integer namespace2,
- Integer namespace3)
+ Integer namespace3,
+ Integer namespace4)
throws Exception {
InternalMapState<String, Integer, Long, Long> mapState =
@@ -179,6 +184,7 @@ public abstract class SavepointStateBackendSwitchTestBase {
mapState.setCurrentNamespace(namespace2);
mapState.put(22L, 22L);
mapState.put(11L, 11L);
+
listState.setCurrentNamespace(namespace2);
listState.add(4L);
listState.add(5L);
@@ -194,6 +200,7 @@ public abstract class SavepointStateBackendSwitchTestBase {
mapState.put(33L, 33L);
mapState.put(44L, 44L);
mapState.put(55L, 55L);
+
valueState.setCurrentNamespace(namespace3);
valueState.update(1239L);
listState.setCurrentNamespace(namespace3);
@@ -201,6 +208,16 @@ public abstract class SavepointStateBackendSwitchTestBase {
listState.add(2L);
listState.add(3L);
+ mapState.setCurrentNamespace(namespace4);
+ mapState.put(1L, 1L);
+ // HEAP state backend will keep an empty map as an entry in the underlying State Table
+ // we should skip such entries when serializing
+ Iterator<Map.Entry<Long, Long>> iterator = mapState.iterator();
+ while (iterator.hasNext()) {
+ iterator.next();
+ iterator.remove();
+ }
+
KeyGroupedInternalPriorityQueue<TimerHeapInternalTimer<String, Integer>> priorityQueue =
keyedBackend.create(
"event-time",
@@ -234,9 +251,10 @@ public abstract class SavepointStateBackendSwitchTestBase {
Integer namespace1,
Integer namespace2,
Integer namespace3,
+ Integer namespace4,
CheckpointableKeyedStateBackend<String> keyedBackend)
throws Exception {
- InternalMapState<String, Integer, Long, Long> state =
+ InternalMapState<String, Integer, Long, Long> mapState =
keyedBackend.createInternalState(IntSerializer.INSTANCE, mapStateDescriptor);
InternalValueState<String, Integer, Long> valueState =
@@ -246,35 +264,38 @@ public abstract class SavepointStateBackendSwitchTestBase {
keyedBackend.createInternalState(IntSerializer.INSTANCE, listStateDescriptor);
keyedBackend.setCurrentKey("abc");
- state.setCurrentNamespace(namespace1);
- assertEquals(33L, (long) state.get(33L));
- assertEquals(55L, (long) state.get(55L));
- assertEquals(2, getStateSize(state));
-
- state.setCurrentNamespace(namespace2);
- assertEquals(22L, (long) state.get(22L));
- assertEquals(11L, (long) state.get(11L));
- assertEquals(2, getStateSize(state));
+ mapState.setCurrentNamespace(namespace1);
+ assertEquals(33L, (long) mapState.get(33L));
+ assertEquals(55L, (long) mapState.get(55L));
+ assertEquals(2, getStateSize(mapState));
+
+ mapState.setCurrentNamespace(namespace2);
+ assertEquals(22L, (long) mapState.get(22L));
+ assertEquals(11L, (long) mapState.get(11L));
+ assertEquals(2, getStateSize(mapState));
listState.setCurrentNamespace(namespace2);
assertThat(listState.get(), contains(4L, 5L, 6L));
- state.setCurrentNamespace(namespace3);
- assertEquals(44L, (long) state.get(44L));
- assertEquals(1, getStateSize(state));
+ mapState.setCurrentNamespace(namespace3);
+ assertEquals(44L, (long) mapState.get(44L));
+ assertEquals(1, getStateSize(mapState));
keyedBackend.setCurrentKey("mno");
- state.setCurrentNamespace(namespace3);
- assertEquals(11L, (long) state.get(11L));
- assertEquals(22L, (long) state.get(22L));
- assertEquals(33L, (long) state.get(33L));
- assertEquals(44L, (long) state.get(44L));
- assertEquals(55L, (long) state.get(55L));
- assertEquals(5, getStateSize(state));
+ mapState.setCurrentNamespace(namespace3);
+ assertEquals(11L, (long) mapState.get(11L));
+ assertEquals(22L, (long) mapState.get(22L));
+ assertEquals(33L, (long) mapState.get(33L));
+ assertEquals(44L, (long) mapState.get(44L));
+ assertEquals(55L, (long) mapState.get(55L));
+ assertEquals(5, getStateSize(mapState));
valueState.setCurrentNamespace(namespace3);
assertEquals(1239L, (long) valueState.value());
listState.setCurrentNamespace(namespace3);
assertThat(listState.get(), contains(1L, 2L, 3L));
+ mapState.setCurrentNamespace(namespace4);
+ assertThat(mapState.isEmpty(), is(true));
+
KeyGroupedInternalPriorityQueue<TimerHeapInternalTimer<String, Integer>> priorityQueue =
keyedBackend.create(
"event-time",