2 * Copyright (c) 2015 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.controller.cluster.datastore;
10 import akka.actor.ActorRef;
11 import akka.util.Timeout;
12 import com.google.common.annotations.VisibleForTesting;
13 import com.google.common.base.MoreObjects;
14 import com.google.common.base.Optional;
15 import com.google.common.base.Preconditions;
16 import com.google.common.base.Stopwatch;
17 import com.google.common.base.Ticker;
18 import com.google.common.base.Verify;
19 import com.google.common.collect.ImmutableList;
20 import com.google.common.collect.ImmutableMap;
21 import com.google.common.collect.ImmutableMap.Builder;
22 import com.google.common.collect.Iterables;
23 import com.google.common.primitives.UnsignedLong;
24 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
26 import java.io.IOException;
27 import java.util.AbstractMap.SimpleEntry;
28 import java.util.ArrayDeque;
29 import java.util.ArrayList;
30 import java.util.Collection;
31 import java.util.HashMap;
32 import java.util.Iterator;
34 import java.util.Map.Entry;
35 import java.util.Queue;
36 import java.util.concurrent.ExecutionException;
37 import java.util.concurrent.TimeUnit;
38 import java.util.concurrent.TimeoutException;
39 import java.util.function.Consumer;
40 import java.util.function.UnaryOperator;
41 import javax.annotation.Nonnull;
42 import javax.annotation.concurrent.NotThreadSafe;
43 import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier;
44 import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier;
45 import org.opendaylight.controller.cluster.datastore.DataTreeCohortActorRegistry.CohortRegistryCommand;
46 import org.opendaylight.controller.cluster.datastore.ShardDataTreeCohort.State;
47 import org.opendaylight.controller.cluster.datastore.persisted.CommitTransactionPayload;
48 import org.opendaylight.controller.cluster.datastore.persisted.MetadataShardDataTreeSnapshot;
49 import org.opendaylight.controller.cluster.datastore.persisted.ShardDataTreeSnapshot;
50 import org.opendaylight.controller.cluster.datastore.persisted.ShardDataTreeSnapshotMetadata;
51 import org.opendaylight.controller.cluster.datastore.utils.DataTreeModificationOutput;
52 import org.opendaylight.controller.cluster.datastore.utils.PruningDataTreeModification;
53 import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload;
54 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope;
55 import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener;
56 import org.opendaylight.controller.md.sal.common.api.data.OptimisticLockFailedException;
57 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
58 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener;
59 import org.opendaylight.controller.md.sal.dom.store.impl.DataChangeListenerRegistration;
60 import org.opendaylight.yangtools.concepts.Identifier;
61 import org.opendaylight.yangtools.concepts.ListenerRegistration;
62 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
63 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
64 import org.opendaylight.yangtools.yang.data.api.schema.tree.ConflictingModificationAppliedException;
65 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
66 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateTip;
67 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidates;
68 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
69 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
70 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeTip;
71 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
72 import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType;
73 import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTree;
74 import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTreeTip;
75 import org.opendaylight.yangtools.yang.data.api.schema.tree.TreeType;
76 import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory;
77 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
78 import org.slf4j.Logger;
79 import org.slf4j.LoggerFactory;
80 import scala.concurrent.duration.Duration;
83 * Internal shard state, similar to a DOMStore, but optimized for use in the actor system,
84 * e.g. it does not expose public interfaces and assumes it is only ever called from a
88 * This class is not part of the API contract and is subject to change at any time.
91 public class ShardDataTree extends ShardDataTreeTransactionParent {
92 private static final class CommitEntry {
93 final SimpleShardDataTreeCohort cohort;
96 CommitEntry(final SimpleShardDataTreeCohort cohort, final long now) {
97 this.cohort = Preconditions.checkNotNull(cohort);
102 private static final Timeout COMMIT_STEP_TIMEOUT = new Timeout(Duration.create(5, TimeUnit.SECONDS));
103 private static final Logger LOG = LoggerFactory.getLogger(ShardDataTree.class);
105 private final Map<LocalHistoryIdentifier, ShardDataTreeTransactionChain> transactionChains = new HashMap<>();
106 private final DataTreeCohortActorRegistry cohortRegistry = new DataTreeCohortActorRegistry();
107 private final Queue<CommitEntry> pendingTransactions = new ArrayDeque<>();
108 private final Queue<CommitEntry> pendingCommits = new ArrayDeque<>();
109 private final Queue<CommitEntry> pendingFinishCommits = new ArrayDeque<>();
110 private final ShardDataTreeChangeListenerPublisher treeChangeListenerPublisher;
111 private final ShardDataChangeListenerPublisher dataChangeListenerPublisher;
112 private final Collection<ShardDataTreeMetadata<?>> metadata;
113 private final TipProducingDataTree dataTree;
114 private final String logContext;
115 private final Shard shard;
116 private Runnable runOnPendingTransactionsComplete;
119 * Optimistic {@link DataTreeCandidate} preparation. Since our DataTree implementation is a
120 * {@link TipProducingDataTree}, each {@link DataTreeCandidate} is also a {@link DataTreeTip}, e.g. another
121 * candidate can be prepared on top of it. They still need to be committed in sequence. Here we track the current
122 * tip of the data tree, which is the last DataTreeCandidate we have in flight, or the DataTree itself.
124 private TipProducingDataTreeTip tip;
126 private SchemaContext schemaContext;
128 public ShardDataTree(final Shard shard, final SchemaContext schemaContext, final TipProducingDataTree dataTree,
129 final ShardDataTreeChangeListenerPublisher treeChangeListenerPublisher,
130 final ShardDataChangeListenerPublisher dataChangeListenerPublisher, final String logContext,
131 final ShardDataTreeMetadata<?>... metadata) {
132 this.dataTree = Preconditions.checkNotNull(dataTree);
133 updateSchemaContext(schemaContext);
135 this.shard = Preconditions.checkNotNull(shard);
136 this.treeChangeListenerPublisher = Preconditions.checkNotNull(treeChangeListenerPublisher);
137 this.dataChangeListenerPublisher = Preconditions.checkNotNull(dataChangeListenerPublisher);
138 this.logContext = Preconditions.checkNotNull(logContext);
139 this.metadata = ImmutableList.copyOf(metadata);
143 public ShardDataTree(final Shard shard, final SchemaContext schemaContext, final TreeType treeType,
144 final YangInstanceIdentifier root,
145 final ShardDataTreeChangeListenerPublisher treeChangeListenerPublisher,
146 final ShardDataChangeListenerPublisher dataChangeListenerPublisher, final String logContext) {
147 this(shard, schemaContext, InMemoryDataTreeFactory.getInstance().create(treeType, root),
148 treeChangeListenerPublisher, dataChangeListenerPublisher, logContext);
152 public ShardDataTree(final Shard shard, final SchemaContext schemaContext, final TreeType treeType) {
153 this(shard, schemaContext, treeType, YangInstanceIdentifier.EMPTY,
154 new DefaultShardDataTreeChangeListenerPublisher(),
155 new DefaultShardDataChangeListenerPublisher(), "");
158 final String logContext() {
162 final Ticker ticker() {
163 return shard.ticker();
166 public TipProducingDataTree getDataTree() {
170 SchemaContext getSchemaContext() {
171 return schemaContext;
174 void updateSchemaContext(final SchemaContext newSchemaContext) {
175 dataTree.setSchemaContext(newSchemaContext);
176 this.schemaContext = Preconditions.checkNotNull(newSchemaContext);
180 * Take a snapshot of current state for later recovery.
182 * @return A state snapshot
184 @Nonnull ShardDataTreeSnapshot takeStateSnapshot() {
185 final NormalizedNode<?, ?> rootNode = dataTree.takeSnapshot().readNode(YangInstanceIdentifier.EMPTY).get();
186 final Builder<Class<? extends ShardDataTreeSnapshotMetadata<?>>, ShardDataTreeSnapshotMetadata<?>> metaBuilder =
187 ImmutableMap.builder();
189 for (ShardDataTreeMetadata<?> m : metadata) {
190 final ShardDataTreeSnapshotMetadata<?> meta = m.toSnapshot();
192 metaBuilder.put(meta.getType(), meta);
196 return new MetadataShardDataTreeSnapshot(rootNode, metaBuilder.build());
199 private boolean anyPendingTransactions() {
200 return !pendingTransactions.isEmpty() || !pendingCommits.isEmpty() || !pendingFinishCommits.isEmpty();
203 private void applySnapshot(@Nonnull final ShardDataTreeSnapshot snapshot,
204 final UnaryOperator<DataTreeModification> wrapper) throws DataValidationFailedException {
205 final Stopwatch elapsed = Stopwatch.createStarted();
207 if (anyPendingTransactions()) {
208 LOG.warn("{}: applying state snapshot with pending transactions", logContext);
211 final Map<Class<? extends ShardDataTreeSnapshotMetadata<?>>, ShardDataTreeSnapshotMetadata<?>> snapshotMeta;
212 if (snapshot instanceof MetadataShardDataTreeSnapshot) {
213 snapshotMeta = ((MetadataShardDataTreeSnapshot) snapshot).getMetadata();
215 snapshotMeta = ImmutableMap.of();
218 for (ShardDataTreeMetadata<?> m : metadata) {
219 final ShardDataTreeSnapshotMetadata<?> s = snapshotMeta.get(m.getSupportedType());
227 final DataTreeModification mod = wrapper.apply(dataTree.takeSnapshot().newModification());
228 // delete everything first
229 mod.delete(YangInstanceIdentifier.EMPTY);
231 final java.util.Optional<NormalizedNode<?, ?>> maybeNode = snapshot.getRootNode();
232 if (maybeNode.isPresent()) {
233 // Add everything from the remote node back
234 mod.write(YangInstanceIdentifier.EMPTY, maybeNode.get());
238 final DataTreeModification unwrapped = unwrap(mod);
239 dataTree.validate(unwrapped);
240 DataTreeCandidateTip candidate = dataTree.prepare(unwrapped);
241 dataTree.commit(candidate);
242 notifyListeners(candidate);
244 LOG.debug("{}: state snapshot applied in %s", logContext, elapsed);
248 * Apply a snapshot coming from the leader. This method assumes the leader and follower SchemaContexts match and
249 * does not perform any pruning.
251 * @param snapshot Snapshot that needs to be applied
252 * @throws DataValidationFailedException when the snapshot fails to apply
254 void applySnapshot(@Nonnull final ShardDataTreeSnapshot snapshot) throws DataValidationFailedException {
255 applySnapshot(snapshot, UnaryOperator.identity());
258 private PruningDataTreeModification wrapWithPruning(final DataTreeModification delegate) {
259 return new PruningDataTreeModification(delegate, dataTree, schemaContext);
262 private static DataTreeModification unwrap(final DataTreeModification modification) {
263 if (modification instanceof PruningDataTreeModification) {
264 return ((PruningDataTreeModification)modification).delegate();
270 * Apply a snapshot coming from recovery. This method does not assume the SchemaContexts match and performs data
271 * pruning in an attempt to adjust the state to our current SchemaContext.
273 * @param snapshot Snapshot that needs to be applied
274 * @throws DataValidationFailedException when the snapshot fails to apply
276 void applyRecoverySnapshot(final @Nonnull ShardDataTreeSnapshot snapshot) throws DataValidationFailedException {
277 applySnapshot(snapshot, this::wrapWithPruning);
280 @SuppressWarnings("checkstyle:IllegalCatch")
281 private void applyRecoveryCandidate(final DataTreeCandidate candidate) throws DataValidationFailedException {
282 final PruningDataTreeModification mod = wrapWithPruning(dataTree.takeSnapshot().newModification());
283 DataTreeCandidates.applyToModification(mod, candidate);
286 final DataTreeModification unwrapped = mod.delegate();
287 LOG.trace("{}: Applying recovery modification {}", logContext, unwrapped);
290 dataTree.validate(unwrapped);
291 dataTree.commit(dataTree.prepare(unwrapped));
292 } catch (Exception e) {
293 File file = new File(System.getProperty("karaf.data", "."),
294 "failed-recovery-payload-" + logContext + ".out");
295 DataTreeModificationOutput.toFile(file, unwrapped);
296 throw new IllegalStateException(String.format(
297 "%s: Failed to apply recovery payload. Modification data was written to file %s",
298 logContext, file), e);
303 * Apply a payload coming from recovery. This method does not assume the SchemaContexts match and performs data
304 * pruning in an attempt to adjust the state to our current SchemaContext.
306 * @param payload Payload
307 * @throws IOException when the snapshot fails to deserialize
308 * @throws DataValidationFailedException when the snapshot fails to apply
310 void applyRecoveryPayload(final @Nonnull Payload payload) throws IOException, DataValidationFailedException {
311 if (payload instanceof CommitTransactionPayload) {
312 final Entry<TransactionIdentifier, DataTreeCandidate> e =
313 ((CommitTransactionPayload) payload).getCandidate();
314 applyRecoveryCandidate(e.getValue());
315 allMetadataCommittedTransaction(e.getKey());
316 } else if (payload instanceof DataTreeCandidatePayload) {
317 applyRecoveryCandidate(((DataTreeCandidatePayload) payload).getCandidate());
319 LOG.debug("{}: ignoring unhandled payload {}", logContext, payload);
323 private void applyReplicatedCandidate(final Identifier identifier, final DataTreeCandidate foreign)
324 throws DataValidationFailedException {
325 LOG.debug("{}: Applying foreign transaction {}", logContext, identifier);
327 final DataTreeModification mod = dataTree.takeSnapshot().newModification();
328 DataTreeCandidates.applyToModification(mod, foreign);
331 LOG.trace("{}: Applying foreign modification {}", logContext, mod);
332 dataTree.validate(mod);
333 final DataTreeCandidate candidate = dataTree.prepare(mod);
334 dataTree.commit(candidate);
336 notifyListeners(candidate);
340 * Apply a payload coming from the leader, which could actually be us. This method assumes the leader and follower
341 * SchemaContexts match and does not perform any pruning.
343 * @param identifier Payload identifier as returned from RaftActor
344 * @param payload Payload
345 * @throws IOException when the snapshot fails to deserialize
346 * @throws DataValidationFailedException when the snapshot fails to apply
348 void applyReplicatedPayload(final Identifier identifier, final Payload payload) throws IOException,
349 DataValidationFailedException {
351 * This is a bit more involved than it needs to be due to to the fact we do not want to be touching the payload
352 * if we are the leader and it has originated with us.
354 * The identifier will only ever be non-null when we were the leader which achieved consensus. Unfortunately,
355 * though, this may not be the case anymore, as we are being called some time afterwards and we may not be
356 * acting in that capacity anymore.
358 * In any case, we know that this is an entry coming from replication, hence we can be sure we will not observe
359 * pre-Boron state -- which limits the number of options here.
361 if (payload instanceof CommitTransactionPayload) {
362 if (identifier == null) {
363 final Entry<TransactionIdentifier, DataTreeCandidate> e =
364 ((CommitTransactionPayload) payload).getCandidate();
365 applyReplicatedCandidate(e.getKey(), e.getValue());
366 allMetadataCommittedTransaction(e.getKey());
368 Verify.verify(identifier instanceof TransactionIdentifier);
369 payloadReplicationComplete((TransactionIdentifier) identifier);
372 LOG.warn("{}: ignoring unhandled identifier {} payload {}", logContext, identifier, payload);
376 private void payloadReplicationComplete(final TransactionIdentifier txId) {
377 final CommitEntry current = pendingFinishCommits.peek();
378 if (current == null) {
379 LOG.warn("{}: No outstanding transactions, ignoring consensus on transaction {}", logContext, txId);
383 if (!current.cohort.getIdentifier().equals(txId)) {
384 LOG.debug("{}: Head of pendingFinishCommits queue is {}, ignoring consensus on transaction {}", logContext,
385 current.cohort.getIdentifier(), txId);
389 finishCommit(current.cohort);
392 private void allMetadataCommittedTransaction(final TransactionIdentifier txId) {
393 for (ShardDataTreeMetadata<?> m : metadata) {
394 m.onTransactionCommitted(txId);
398 ShardDataTreeTransactionChain ensureTransactionChain(final LocalHistoryIdentifier localHistoryIdentifier) {
399 ShardDataTreeTransactionChain chain = transactionChains.get(localHistoryIdentifier);
401 chain = new ShardDataTreeTransactionChain(localHistoryIdentifier, this);
402 transactionChains.put(localHistoryIdentifier, chain);
408 ReadOnlyShardDataTreeTransaction newReadOnlyTransaction(final TransactionIdentifier txId) {
409 if (txId.getHistoryId().getHistoryId() == 0) {
410 return new ReadOnlyShardDataTreeTransaction(txId, dataTree.takeSnapshot());
413 return ensureTransactionChain(txId.getHistoryId()).newReadOnlyTransaction(txId);
416 ReadWriteShardDataTreeTransaction newReadWriteTransaction(final TransactionIdentifier txId) {
417 if (txId.getHistoryId().getHistoryId() == 0) {
418 return new ReadWriteShardDataTreeTransaction(ShardDataTree.this, txId, dataTree.takeSnapshot()
422 return ensureTransactionChain(txId.getHistoryId()).newReadWriteTransaction(txId);
426 public void notifyListeners(final DataTreeCandidate candidate) {
427 treeChangeListenerPublisher.publishChanges(candidate, logContext);
428 dataChangeListenerPublisher.publishChanges(candidate, logContext);
431 void notifyOfInitialData(final DataChangeListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier,
432 NormalizedNode<?, ?>>> listenerReg, final Optional<DataTreeCandidate> currentState) {
433 if (currentState.isPresent()) {
434 ShardDataChangeListenerPublisher localPublisher = dataChangeListenerPublisher.newInstance();
435 localPublisher.registerDataChangeListener(listenerReg.getPath(), listenerReg.getInstance(),
436 listenerReg.getScope());
437 localPublisher.publishChanges(currentState.get(), logContext);
441 void notifyOfInitialData(final YangInstanceIdentifier path, final DOMDataTreeChangeListener listener,
442 final Optional<DataTreeCandidate> currentState) {
443 if (currentState.isPresent()) {
444 ShardDataTreeChangeListenerPublisher localPublisher = treeChangeListenerPublisher.newInstance();
445 localPublisher.registerTreeChangeListener(path, listener);
446 localPublisher.publishChanges(currentState.get(), logContext);
450 void closeAllTransactionChains() {
451 for (ShardDataTreeTransactionChain chain : transactionChains.values()) {
455 transactionChains.clear();
458 void closeTransactionChain(final LocalHistoryIdentifier transactionChainId) {
459 final ShardDataTreeTransactionChain chain = transactionChains.remove(transactionChainId);
463 LOG.debug("{}: Closing non-existent transaction chain {}", logContext, transactionChainId);
467 Entry<DataChangeListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>>,
468 Optional<DataTreeCandidate>> registerChangeListener(final YangInstanceIdentifier path,
469 final AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>> listener,
470 final DataChangeScope scope) {
471 DataChangeListenerRegistration<AsyncDataChangeListener<YangInstanceIdentifier, NormalizedNode<?, ?>>> reg =
472 dataChangeListenerPublisher.registerDataChangeListener(path, listener, scope);
474 return new SimpleEntry<>(reg, readCurrentData());
477 private Optional<DataTreeCandidate> readCurrentData() {
478 final Optional<NormalizedNode<?, ?>> currentState =
479 dataTree.takeSnapshot().readNode(YangInstanceIdentifier.EMPTY);
480 return currentState.isPresent() ? Optional.of(DataTreeCandidates.fromNormalizedNode(
481 YangInstanceIdentifier.EMPTY, currentState.get())) : Optional.<DataTreeCandidate>absent();
484 public Entry<ListenerRegistration<DOMDataTreeChangeListener>, Optional<DataTreeCandidate>>
485 registerTreeChangeListener(final YangInstanceIdentifier path, final DOMDataTreeChangeListener listener) {
486 final ListenerRegistration<DOMDataTreeChangeListener> reg =
487 treeChangeListenerPublisher.registerTreeChangeListener(path, listener);
489 return new SimpleEntry<>(reg, readCurrentData());
493 return pendingTransactions.size() + pendingCommits.size() + pendingFinishCommits.size();
497 void abortTransaction(final AbstractShardDataTreeTransaction<?> transaction) {
502 ShardDataTreeCohort finishTransaction(final ReadWriteShardDataTreeTransaction transaction) {
503 final DataTreeModification snapshot = transaction.getSnapshot();
506 return createReadyCohort(transaction.getIdentifier(), snapshot);
509 public Optional<NormalizedNode<?, ?>> readNode(final YangInstanceIdentifier path) {
510 return dataTree.takeSnapshot().readNode(path);
513 DataTreeSnapshot takeSnapshot() {
514 return dataTree.takeSnapshot();
518 public DataTreeModification newModification() {
519 return dataTree.takeSnapshot().newModification();
523 * Commits a modification.
525 * @deprecated This method violates DataTree containment and will be removed.
529 public DataTreeCandidate commit(final DataTreeModification modification) throws DataValidationFailedException {
530 // Direct modification commit is a utility, which cannot be used while we have transactions in-flight
531 Preconditions.checkState(tip == dataTree, "Cannot modify data tree while transacgitons are pending");
533 modification.ready();
534 dataTree.validate(modification);
535 DataTreeCandidate candidate = dataTree.prepare(modification);
536 dataTree.commit(candidate);
540 public Collection<ShardDataTreeCohort> getAndClearPendingTransactions() {
541 Collection<ShardDataTreeCohort> ret = new ArrayList<>(getQueueSize());
543 for (CommitEntry entry: pendingFinishCommits) {
544 ret.add(entry.cohort);
547 for (CommitEntry entry: pendingCommits) {
548 ret.add(entry.cohort);
551 for (CommitEntry entry: pendingTransactions) {
552 ret.add(entry.cohort);
555 pendingFinishCommits.clear();
556 pendingCommits.clear();
557 pendingTransactions.clear();
562 @SuppressWarnings("checkstyle:IllegalCatch")
563 private void processNextPendingTransaction() {
564 processNextPending(pendingTransactions, State.CAN_COMMIT_PENDING, entry -> {
565 final SimpleShardDataTreeCohort cohort = entry.cohort;
566 final DataTreeModification modification = cohort.getDataTreeModification();
568 LOG.debug("{}: Validating transaction {}", logContext, cohort.getIdentifier());
571 tip.validate(modification);
572 LOG.debug("{}: Transaction {} validated", logContext, cohort.getIdentifier());
573 cohort.successfulCanCommit();
574 entry.lastAccess = shard.ticker().read();
576 } catch (ConflictingModificationAppliedException e) {
577 LOG.warn("{}: Store Tx {}: Conflicting modification for path {}.", logContext, cohort.getIdentifier(),
579 cause = new OptimisticLockFailedException("Optimistic lock failed.", e);
580 } catch (DataValidationFailedException e) {
581 LOG.warn("{}: Store Tx {}: Data validation failed for path {}.", logContext, cohort.getIdentifier(),
584 // For debugging purposes, allow dumping of the modification. Coupled with the above
585 // precondition log, it should allow us to understand what went on.
586 LOG.debug("{}: Store Tx {}: modifications: {} tree: {}", cohort.getIdentifier(), modification,
588 cause = new TransactionCommitFailedException("Data did not pass validation.", e);
589 } catch (Exception e) {
590 LOG.warn("{}: Unexpected failure in validation phase", logContext, e);
594 // Failure path: propagate the failure, remove the transaction from the queue and loop to the next one
595 pendingTransactions.poll().cohort.failedCanCommit(cause);
599 private void processNextPending() {
600 processNextPendingFinishCommit();
601 processNextPendingCommit();
602 processNextPendingTransaction();
605 private void processNextPending(Queue<CommitEntry> queue, State allowedState, Consumer<CommitEntry> processor) {
606 while (!queue.isEmpty()) {
607 final CommitEntry entry = queue.peek();
608 final SimpleShardDataTreeCohort cohort = entry.cohort;
610 if (cohort.isFailed()) {
611 LOG.debug("{}: Removing failed transaction {}", logContext, cohort.getIdentifier());
616 if (cohort.getState() == allowedState) {
617 processor.accept(entry);
623 maybeRunOperationOnPendingTransactionsComplete();
626 private void processNextPendingCommit() {
627 processNextPending(pendingCommits, State.COMMIT_PENDING,
628 entry -> startCommit(entry.cohort, entry.cohort.getCandidate()));
631 private void processNextPendingFinishCommit() {
632 processNextPending(pendingFinishCommits, State.FINISH_COMMIT_PENDING,
633 entry -> payloadReplicationComplete(entry.cohort.getIdentifier()));
636 private boolean peekNextPendingCommit() {
637 final CommitEntry first = pendingCommits.peek();
638 return first != null && first.cohort.getState() == State.COMMIT_PENDING;
641 void startCanCommit(final SimpleShardDataTreeCohort cohort) {
642 final SimpleShardDataTreeCohort current = pendingTransactions.peek().cohort;
643 if (!cohort.equals(current)) {
644 LOG.debug("{}: Transaction {} scheduled for canCommit step", logContext, cohort.getIdentifier());
648 processNextPendingTransaction();
651 private void failPreCommit(final Exception cause) {
652 shard.getShardMBean().incrementFailedTransactionsCount();
653 pendingTransactions.poll().cohort.failedPreCommit(cause);
654 processNextPendingTransaction();
657 @SuppressWarnings("checkstyle:IllegalCatch")
658 void startPreCommit(final SimpleShardDataTreeCohort cohort) {
659 final CommitEntry entry = pendingTransactions.peek();
660 Preconditions.checkState(entry != null, "Attempted to pre-commit of %s when no transactions pending", cohort);
662 final SimpleShardDataTreeCohort current = entry.cohort;
663 Verify.verify(cohort.equals(current), "Attempted to pre-commit %s while %s is pending", cohort, current);
665 LOG.debug("{}: Preparing transaction {}", logContext, current.getIdentifier());
667 final DataTreeCandidateTip candidate;
669 candidate = tip.prepare(cohort.getDataTreeModification());
670 cohort.userPreCommit(candidate);
671 } catch (ExecutionException | TimeoutException | RuntimeException e) {
676 // Set the tip of the data tree.
677 tip = Verify.verifyNotNull(candidate);
679 entry.lastAccess = shard.ticker().read();
681 pendingTransactions.remove();
682 pendingCommits.add(entry);
684 LOG.debug("{}: Transaction {} prepared", logContext, current.getIdentifier());
686 cohort.successfulPreCommit(candidate);
688 processNextPendingTransaction();
691 private void failCommit(final Exception cause) {
692 shard.getShardMBean().incrementFailedTransactionsCount();
693 pendingFinishCommits.poll().cohort.failedCommit(cause);
694 processNextPending();
697 @SuppressWarnings("checkstyle:IllegalCatch")
698 private void finishCommit(final SimpleShardDataTreeCohort cohort) {
699 final TransactionIdentifier txId = cohort.getIdentifier();
700 final DataTreeCandidate candidate = cohort.getCandidate();
702 LOG.debug("{}: Resuming commit of transaction {}", logContext, txId);
704 if (tip == candidate) {
705 // All pending candidates have been committed, reset the tip to the data tree.
710 dataTree.commit(candidate);
711 } catch (Exception e) {
712 LOG.error("{}: Failed to commit transaction {}", logContext, txId, e);
717 shard.getShardMBean().incrementCommittedTransactionCount();
718 shard.getShardMBean().setLastCommittedTransactionTime(System.currentTimeMillis());
720 // FIXME: propagate journal index
721 pendingFinishCommits.poll().cohort.successfulCommit(UnsignedLong.ZERO);
723 LOG.trace("{}: Transaction {} committed, proceeding to notify", logContext, txId);
724 notifyListeners(candidate);
726 processNextPending();
729 void startCommit(final SimpleShardDataTreeCohort cohort, final DataTreeCandidate candidate) {
730 final CommitEntry entry = pendingCommits.peek();
731 Preconditions.checkState(entry != null, "Attempted to start commit of %s when no transactions pending", cohort);
733 final SimpleShardDataTreeCohort current = entry.cohort;
734 if (!cohort.equals(current)) {
735 LOG.debug("{}: Transaction {} scheduled for commit step", logContext, cohort.getIdentifier());
739 LOG.debug("{}: Starting commit for transaction {}", logContext, current.getIdentifier());
741 final TransactionIdentifier txId = cohort.getIdentifier();
742 if (shard.canSkipPayload() || candidate.getRootNode().getModificationType() == ModificationType.UNMODIFIED) {
743 LOG.debug("{}: No replication required, proceeding to finish commit", logContext);
744 pendingCommits.remove();
745 pendingFinishCommits.add(entry);
746 cohort.finishCommitPending();
747 payloadReplicationComplete(txId);
751 final Payload payload;
753 payload = CommitTransactionPayload.create(txId, candidate);
754 } catch (IOException e) {
755 LOG.error("{}: Failed to encode transaction {} candidate {}", logContext, txId, candidate, e);
756 pendingCommits.poll().cohort.failedCommit(e);
757 processNextPending();
761 // We process next transactions pending canCommit before we call persistPayload to possibly progress subsequent
762 // transactions to the COMMIT_PENDING state so the payloads can be batched for replication. This is done for
763 // single-shard transactions that immediately transition from canCommit to preCommit to commit. Note that
764 // if the next pending transaction is progressed to COMMIT_PENDING and this method (startCommit) is called,
765 // the next transaction will not attempt to replicate b/c the current transaction is still at the head of the
766 // pendingCommits queue.
767 processNextPendingTransaction();
769 // After processing next pending transactions, we can now remove the current transaction from pendingCommits.
770 // Note this must be done before the call to peekNextPendingCommit below so we check the next transaction
771 // in order to properly determine the batchHint flag for the call to persistPayload.
772 pendingCommits.remove();
773 pendingFinishCommits.add(entry);
775 // See if the next transaction is pending commit (ie in the COMMIT_PENDING state) so it can be batched with
776 // this transaction for replication.
777 boolean replicationBatchHint = peekNextPendingCommit();
779 // Once completed, we will continue via payloadReplicationComplete
780 shard.persistPayload(txId, payload, replicationBatchHint);
782 entry.lastAccess = shard.ticker().read();
784 LOG.debug("{}: Transaction {} submitted to persistence", logContext, txId);
786 // Process the next transaction pending commit, if any. If there is one it will be batched with this
787 // transaction for replication.
788 processNextPendingCommit();
791 void processCohortRegistryCommand(final ActorRef sender, final CohortRegistryCommand message) {
792 cohortRegistry.process(sender, message);
796 ShardDataTreeCohort createReadyCohort(final TransactionIdentifier txId,
797 final DataTreeModification modification) {
798 SimpleShardDataTreeCohort cohort = new SimpleShardDataTreeCohort(this, modification, txId,
799 cohortRegistry.createCohort(schemaContext, txId, COMMIT_STEP_TIMEOUT));
800 pendingTransactions.add(new CommitEntry(cohort, shard.ticker().read()));
804 @SuppressFBWarnings(value = "DB_DUPLICATE_SWITCH_CLAUSES", justification = "See inline comments below.")
805 void checkForExpiredTransactions(final long transactionCommitTimeoutMillis) {
806 final long timeout = TimeUnit.MILLISECONDS.toNanos(transactionCommitTimeoutMillis);
807 final long now = shard.ticker().read();
809 final Queue<CommitEntry> currentQueue = !pendingFinishCommits.isEmpty() ? pendingFinishCommits :
810 !pendingCommits.isEmpty() ? pendingCommits : pendingTransactions;
811 final CommitEntry currentTx = currentQueue.peek();
812 if (currentTx != null && currentTx.lastAccess + timeout < now) {
813 LOG.warn("{}: Current transaction {} has timed out after {} ms in state {}", logContext,
814 currentTx.cohort.getIdentifier(), transactionCommitTimeoutMillis, currentTx.cohort.getState());
815 boolean processNext = true;
816 switch (currentTx.cohort.getState()) {
817 case CAN_COMMIT_PENDING:
818 currentQueue.remove().cohort.failedCanCommit(new TimeoutException());
820 case CAN_COMMIT_COMPLETE:
821 // The suppression of the FindBugs "DB_DUPLICATE_SWITCH_CLAUSES" warning pertains to this clause
822 // whose code is duplicated with PRE_COMMIT_COMPLETE. The clauses aren't combined in case the code
823 // in PRE_COMMIT_COMPLETE is changed.
824 currentQueue.remove().cohort.reportFailure(new TimeoutException());
826 case PRE_COMMIT_PENDING:
827 currentQueue.remove().cohort.failedPreCommit(new TimeoutException());
829 case PRE_COMMIT_COMPLETE:
830 // FIXME: this is a legacy behavior problem. Three-phase commit protocol specifies that after we
831 // are ready we should commit the transaction, not abort it. Our current software stack does
832 // not allow us to do that consistently, because we persist at the time of commit, hence
833 // we can end up in a state where we have pre-committed a transaction, then a leader failover
834 // occurred ... the new leader does not see the pre-committed transaction and does not have
835 // a running timer. To fix this we really need two persistence events.
837 // The first one, done at pre-commit time will hold the transaction payload. When consensus
838 // is reached, we exit the pre-commit phase and start the pre-commit timer. Followers do not
839 // apply the state in this event.
841 // The second one, done at commit (or abort) time holds only the transaction identifier and
842 // signals to followers that the state should (or should not) be applied.
844 // In order to make the pre-commit timer working across failovers, though, we need
845 // a per-shard cluster-wide monotonic time, so a follower becoming the leader can accurately
846 // restart the timer.
847 currentQueue.remove().cohort.reportFailure(new TimeoutException());
850 LOG.warn("{}: Transaction {} is still committing, cannot abort", logContext,
851 currentTx.cohort.getIdentifier());
852 currentTx.lastAccess = now;
860 currentQueue.remove();
864 processNextPending();
869 boolean startAbort(final SimpleShardDataTreeCohort cohort) {
870 final Iterator<CommitEntry> it = Iterables.concat(pendingFinishCommits, pendingCommits,
871 pendingTransactions).iterator();
873 LOG.debug("{}: no open transaction while attempting to abort {}", logContext, cohort.getIdentifier());
877 // First entry is special, as it may already be committing
878 final CommitEntry first = it.next();
879 if (cohort.equals(first.cohort)) {
880 if (cohort.getState() != State.COMMIT_PENDING) {
881 LOG.debug("{}: aborting head of queue {} in state {}", logContext, cohort.getIdentifier(),
882 cohort.getIdentifier());
885 if (cohort.getCandidate() != null) {
886 rebaseTransactions(it, dataTree);
889 processNextPending();
893 LOG.warn("{}: transaction {} is committing, skipping abort", logContext, cohort.getIdentifier());
897 TipProducingDataTreeTip newTip = MoreObjects.firstNonNull(first.cohort.getCandidate(), dataTree);
898 while (it.hasNext()) {
899 final CommitEntry e = it.next();
900 if (cohort.equals(e.cohort)) {
901 LOG.debug("{}: aborting queued transaction {}", logContext, cohort.getIdentifier());
904 if (cohort.getCandidate() != null) {
905 rebaseTransactions(it, newTip);
910 newTip = MoreObjects.firstNonNull(e.cohort.getCandidate(), newTip);
914 LOG.debug("{}: aborted transaction {} not found in the queue", logContext, cohort.getIdentifier());
918 @SuppressWarnings("checkstyle:IllegalCatch")
919 private void rebaseTransactions(Iterator<CommitEntry> iter, @Nonnull TipProducingDataTreeTip newTip) {
920 tip = Preconditions.checkNotNull(newTip);
921 while (iter.hasNext()) {
922 final SimpleShardDataTreeCohort cohort = iter.next().cohort;
923 if (cohort.getState() == State.CAN_COMMIT_COMPLETE) {
924 LOG.debug("{}: Revalidating queued transaction {}", logContext, cohort.getIdentifier());
927 tip.validate(cohort.getDataTreeModification());
928 } catch (DataValidationFailedException | RuntimeException e) {
929 LOG.debug("{}: Failed to revalidate queued transaction {}", logContext, cohort.getIdentifier(), e);
930 cohort.reportFailure(e);
932 } else if (cohort.getState() == State.PRE_COMMIT_COMPLETE) {
933 LOG.debug("{}: Repreparing queued transaction {}", logContext, cohort.getIdentifier());
936 tip.validate(cohort.getDataTreeModification());
937 DataTreeCandidateTip candidate = tip.prepare(cohort.getDataTreeModification());
938 cohort.userPreCommit(candidate);
940 cohort.setNewCandidate(candidate);
942 } catch (ExecutionException | TimeoutException | RuntimeException | DataValidationFailedException e) {
943 LOG.debug("{}: Failed to reprepare queued transaction {}", logContext, cohort.getIdentifier(), e);
944 cohort.reportFailure(e);
950 void setRunOnPendingTransactionsComplete(final Runnable operation) {
951 runOnPendingTransactionsComplete = operation;
952 maybeRunOperationOnPendingTransactionsComplete();
955 private void maybeRunOperationOnPendingTransactionsComplete() {
956 if (runOnPendingTransactionsComplete != null && !anyPendingTransactions()) {
957 LOG.debug("{}: Pending transactions complete - running operation {}", logContext,
958 runOnPendingTransactionsComplete);
960 runOnPendingTransactionsComplete.run();
961 runOnPendingTransactionsComplete = null;