X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?p=controller.git;a=blobdiff_plain;f=opendaylight%2Fmd-sal%2Fsal-distributed-datastore%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fcluster%2Fdatastore%2FShardDataTree.java;h=78b49a60ae5cef444b28633fd9b8fe397d117914;hp=56c5eb65bf087c3a0d979de2ecaff7b0a65467a2;hb=823bd74f34ee1c651f1f90daeef386a35c68d431;hpb=1447e0132075bbd3013aa41b98384a373bd82d1a diff --git a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/ShardDataTree.java b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/ShardDataTree.java index 56c5eb65bf..78b49a60ae 100644 --- a/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/ShardDataTree.java +++ b/opendaylight/md-sal/sal-distributed-datastore/src/main/java/org/opendaylight/controller/cluster/datastore/ShardDataTree.java @@ -7,99 +7,444 @@ */ package org.opendaylight.controller.cluster.datastore; +import akka.actor.ActorRef; +import akka.util.Timeout; import com.google.common.annotations.VisibleForTesting; +import com.google.common.base.MoreObjects; import com.google.common.base.Optional; -import com.google.common.base.Strings; +import com.google.common.base.Preconditions; +import com.google.common.base.Stopwatch; +import com.google.common.base.Ticker; +import com.google.common.base.Verify; +import com.google.common.collect.ImmutableList; +import com.google.common.collect.ImmutableMap; +import com.google.common.collect.ImmutableMap.Builder; +import com.google.common.collect.Iterables; +import com.google.common.primitives.UnsignedLong; +import edu.umd.cs.findbugs.annotations.SuppressFBWarnings; +import java.io.File; +import java.io.IOException; import java.util.AbstractMap.SimpleEntry; +import java.util.ArrayDeque; +import java.util.ArrayList; +import java.util.Collection; import java.util.HashMap; +import java.util.Iterator; import java.util.Map; import java.util.Map.Entry; +import java.util.Queue; +import java.util.concurrent.ExecutionException; +import java.util.concurrent.TimeUnit; +import java.util.concurrent.TimeoutException; +import java.util.function.Consumer; +import java.util.function.UnaryOperator; +import javax.annotation.Nonnull; import javax.annotation.concurrent.NotThreadSafe; +import org.opendaylight.controller.cluster.access.concepts.LocalHistoryIdentifier; +import org.opendaylight.controller.cluster.access.concepts.TransactionIdentifier; +import org.opendaylight.controller.cluster.datastore.DataTreeCohortActorRegistry.CohortRegistryCommand; +import org.opendaylight.controller.cluster.datastore.ShardDataTreeCohort.State; +import org.opendaylight.controller.cluster.datastore.persisted.CommitTransactionPayload; +import org.opendaylight.controller.cluster.datastore.persisted.MetadataShardDataTreeSnapshot; +import org.opendaylight.controller.cluster.datastore.persisted.ShardDataTreeSnapshot; +import org.opendaylight.controller.cluster.datastore.persisted.ShardDataTreeSnapshotMetadata; +import org.opendaylight.controller.cluster.datastore.utils.DataTreeModificationOutput; +import org.opendaylight.controller.cluster.datastore.utils.PruningDataTreeModification; +import org.opendaylight.controller.cluster.raft.protobuff.client.messages.Payload; import org.opendaylight.controller.md.sal.common.api.data.AsyncDataBroker.DataChangeScope; import org.opendaylight.controller.md.sal.common.api.data.AsyncDataChangeListener; +import org.opendaylight.controller.md.sal.common.api.data.OptimisticLockFailedException; +import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException; import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener; -import org.opendaylight.controller.md.sal.dom.store.impl.DOMImmutableDataChangeEvent; -import org.opendaylight.controller.md.sal.dom.store.impl.ResolveDataChangeEventsTask; -import org.opendaylight.controller.md.sal.dom.store.impl.tree.ListenerTree; +import org.opendaylight.controller.md.sal.dom.store.impl.DataChangeListenerRegistration; +import org.opendaylight.yangtools.concepts.Identifier; import org.opendaylight.yangtools.concepts.ListenerRegistration; import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier; import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode; +import org.opendaylight.yangtools.yang.data.api.schema.tree.ConflictingModificationAppliedException; import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate; +import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidateTip; import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidates; import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification; +import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot; +import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeTip; import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException; +import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType; import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTree; +import org.opendaylight.yangtools.yang.data.api.schema.tree.TipProducingDataTreeTip; +import org.opendaylight.yangtools.yang.data.api.schema.tree.TreeType; import org.opendaylight.yangtools.yang.data.impl.schema.tree.InMemoryDataTreeFactory; import org.opendaylight.yangtools.yang.model.api.SchemaContext; import org.slf4j.Logger; import org.slf4j.LoggerFactory; +import scala.concurrent.duration.Duration; /** * Internal shard state, similar to a DOMStore, but optimized for use in the actor system, * e.g. it does not expose public interfaces and assumes it is only ever called from a * single thread. * + *

* This class is not part of the API contract and is subject to change at any time. */ @NotThreadSafe -@VisibleForTesting -public final class ShardDataTree extends ShardDataTreeTransactionParent { +public class ShardDataTree extends ShardDataTreeTransactionParent { + private static final class CommitEntry { + final SimpleShardDataTreeCohort cohort; + long lastAccess; + + CommitEntry(final SimpleShardDataTreeCohort cohort, final long now) { + this.cohort = Preconditions.checkNotNull(cohort); + lastAccess = now; + } + } + + private static final Timeout COMMIT_STEP_TIMEOUT = new Timeout(Duration.create(5, TimeUnit.SECONDS)); private static final Logger LOG = LoggerFactory.getLogger(ShardDataTree.class); - private static final ShardDataTreeNotificationManager MANAGER = new ShardDataTreeNotificationManager(); - private final Map transactionChains = new HashMap<>(); - private final ShardDataTreeChangePublisher treeChangePublisher = new ShardDataTreeChangePublisher(); - private final ListenerTree listenerTree = ListenerTree.create(); + + private final Map transactionChains = new HashMap<>(); + private final DataTreeCohortActorRegistry cohortRegistry = new DataTreeCohortActorRegistry(); + private final Queue pendingTransactions = new ArrayDeque<>(); + private final Queue pendingCommits = new ArrayDeque<>(); + private final Queue pendingFinishCommits = new ArrayDeque<>(); + private final ShardDataTreeChangeListenerPublisher treeChangeListenerPublisher; + private final ShardDataChangeListenerPublisher dataChangeListenerPublisher; + private final Collection> metadata; private final TipProducingDataTree dataTree; + private final String logContext; + private final Shard shard; + private Runnable runOnPendingTransactionsComplete; - ShardDataTree(final SchemaContext schemaContext) { - dataTree = InMemoryDataTreeFactory.getInstance().create(); - if (schemaContext != null) { - dataTree.setSchemaContext(schemaContext); - } + /** + * Optimistic {@link DataTreeCandidate} preparation. Since our DataTree implementation is a + * {@link TipProducingDataTree}, each {@link DataTreeCandidate} is also a {@link DataTreeTip}, e.g. another + * candidate can be prepared on top of it. They still need to be committed in sequence. Here we track the current + * tip of the data tree, which is the last DataTreeCandidate we have in flight, or the DataTree itself. + */ + private TipProducingDataTreeTip tip; + + private SchemaContext schemaContext; + + public ShardDataTree(final Shard shard, final SchemaContext schemaContext, final TipProducingDataTree dataTree, + final ShardDataTreeChangeListenerPublisher treeChangeListenerPublisher, + final ShardDataChangeListenerPublisher dataChangeListenerPublisher, final String logContext, + final ShardDataTreeMetadata... metadata) { + this.dataTree = Preconditions.checkNotNull(dataTree); + updateSchemaContext(schemaContext); + + this.shard = Preconditions.checkNotNull(shard); + this.treeChangeListenerPublisher = Preconditions.checkNotNull(treeChangeListenerPublisher); + this.dataChangeListenerPublisher = Preconditions.checkNotNull(dataChangeListenerPublisher); + this.logContext = Preconditions.checkNotNull(logContext); + this.metadata = ImmutableList.copyOf(metadata); + tip = dataTree; + } + + public ShardDataTree(final Shard shard, final SchemaContext schemaContext, final TreeType treeType, + final YangInstanceIdentifier root, + final ShardDataTreeChangeListenerPublisher treeChangeListenerPublisher, + final ShardDataChangeListenerPublisher dataChangeListenerPublisher, final String logContext) { + this(shard, schemaContext, InMemoryDataTreeFactory.getInstance().create(treeType, root), + treeChangeListenerPublisher, dataChangeListenerPublisher, logContext); + } + + @VisibleForTesting + public ShardDataTree(final Shard shard, final SchemaContext schemaContext, final TreeType treeType) { + this(shard, schemaContext, treeType, YangInstanceIdentifier.EMPTY, + new DefaultShardDataTreeChangeListenerPublisher(), + new DefaultShardDataChangeListenerPublisher(), ""); + } + + final String logContext() { + return logContext; } - TipProducingDataTree getDataTree() { + final Ticker ticker() { + return shard.ticker(); + } + + public TipProducingDataTree getDataTree() { return dataTree; } - void updateSchemaContext(final SchemaContext schemaContext) { - dataTree.setSchemaContext(schemaContext); + SchemaContext getSchemaContext() { + return schemaContext; + } + + void updateSchemaContext(final SchemaContext newSchemaContext) { + dataTree.setSchemaContext(newSchemaContext); + this.schemaContext = Preconditions.checkNotNull(newSchemaContext); + } + + /** + * Take a snapshot of current state for later recovery. + * + * @return A state snapshot + */ + @Nonnull ShardDataTreeSnapshot takeStateSnapshot() { + final NormalizedNode rootNode = dataTree.takeSnapshot().readNode(YangInstanceIdentifier.EMPTY).get(); + final Builder>, ShardDataTreeSnapshotMetadata> metaBuilder = + ImmutableMap.builder(); + + for (ShardDataTreeMetadata m : metadata) { + final ShardDataTreeSnapshotMetadata meta = m.toSnapshot(); + if (meta != null) { + metaBuilder.put(meta.getType(), meta); + } + } + + return new MetadataShardDataTreeSnapshot(rootNode, metaBuilder.build()); + } + + private boolean anyPendingTransactions() { + return !pendingTransactions.isEmpty() || !pendingCommits.isEmpty() || !pendingFinishCommits.isEmpty(); + } + + private void applySnapshot(@Nonnull final ShardDataTreeSnapshot snapshot, + final UnaryOperator wrapper) throws DataValidationFailedException { + final Stopwatch elapsed = Stopwatch.createStarted(); + + if (anyPendingTransactions()) { + LOG.warn("{}: applying state snapshot with pending transactions", logContext); + } + + final Map>, ShardDataTreeSnapshotMetadata> snapshotMeta; + if (snapshot instanceof MetadataShardDataTreeSnapshot) { + snapshotMeta = ((MetadataShardDataTreeSnapshot) snapshot).getMetadata(); + } else { + snapshotMeta = ImmutableMap.of(); + } + + for (ShardDataTreeMetadata m : metadata) { + final ShardDataTreeSnapshotMetadata s = snapshotMeta.get(m.getSupportedType()); + if (s != null) { + m.applySnapshot(s); + } else { + m.reset(); + } + } + + final DataTreeModification mod = wrapper.apply(dataTree.takeSnapshot().newModification()); + // delete everything first + mod.delete(YangInstanceIdentifier.EMPTY); + + final java.util.Optional> maybeNode = snapshot.getRootNode(); + if (maybeNode.isPresent()) { + // Add everything from the remote node back + mod.write(YangInstanceIdentifier.EMPTY, maybeNode.get()); + } + mod.ready(); + + final DataTreeModification unwrapped = unwrap(mod); + dataTree.validate(unwrapped); + DataTreeCandidateTip candidate = dataTree.prepare(unwrapped); + dataTree.commit(candidate); + notifyListeners(candidate); + + LOG.debug("{}: state snapshot applied in %s", logContext, elapsed); + } + + /** + * Apply a snapshot coming from the leader. This method assumes the leader and follower SchemaContexts match and + * does not perform any pruning. + * + * @param snapshot Snapshot that needs to be applied + * @throws DataValidationFailedException when the snapshot fails to apply + */ + void applySnapshot(@Nonnull final ShardDataTreeSnapshot snapshot) throws DataValidationFailedException { + applySnapshot(snapshot, UnaryOperator.identity()); + } + + private PruningDataTreeModification wrapWithPruning(final DataTreeModification delegate) { + return new PruningDataTreeModification(delegate, dataTree, schemaContext); + } + + private static DataTreeModification unwrap(final DataTreeModification modification) { + if (modification instanceof PruningDataTreeModification) { + return ((PruningDataTreeModification)modification).delegate(); + } + return modification; + } + + /** + * Apply a snapshot coming from recovery. This method does not assume the SchemaContexts match and performs data + * pruning in an attempt to adjust the state to our current SchemaContext. + * + * @param snapshot Snapshot that needs to be applied + * @throws DataValidationFailedException when the snapshot fails to apply + */ + void applyRecoverySnapshot(final @Nonnull ShardDataTreeSnapshot snapshot) throws DataValidationFailedException { + applySnapshot(snapshot, this::wrapWithPruning); + } + + @SuppressWarnings("checkstyle:IllegalCatch") + private void applyRecoveryCandidate(final DataTreeCandidate candidate) throws DataValidationFailedException { + final PruningDataTreeModification mod = wrapWithPruning(dataTree.takeSnapshot().newModification()); + DataTreeCandidates.applyToModification(mod, candidate); + mod.ready(); + + final DataTreeModification unwrapped = mod.delegate(); + LOG.trace("{}: Applying recovery modification {}", logContext, unwrapped); + + try { + dataTree.validate(unwrapped); + dataTree.commit(dataTree.prepare(unwrapped)); + } catch (Exception e) { + File file = new File(System.getProperty("karaf.data", "."), + "failed-recovery-payload-" + logContext + ".out"); + DataTreeModificationOutput.toFile(file, unwrapped); + throw new IllegalStateException(String.format( + "%s: Failed to apply recovery payload. Modification data was written to file %s", + logContext, file), e); + } + } + + /** + * Apply a payload coming from recovery. This method does not assume the SchemaContexts match and performs data + * pruning in an attempt to adjust the state to our current SchemaContext. + * + * @param payload Payload + * @throws IOException when the snapshot fails to deserialize + * @throws DataValidationFailedException when the snapshot fails to apply + */ + void applyRecoveryPayload(final @Nonnull Payload payload) throws IOException, DataValidationFailedException { + if (payload instanceof CommitTransactionPayload) { + final Entry e = + ((CommitTransactionPayload) payload).getCandidate(); + applyRecoveryCandidate(e.getValue()); + allMetadataCommittedTransaction(e.getKey()); + } else if (payload instanceof DataTreeCandidatePayload) { + applyRecoveryCandidate(((DataTreeCandidatePayload) payload).getCandidate()); + } else { + LOG.debug("{}: ignoring unhandled payload {}", logContext, payload); + } + } + + private void applyReplicatedCandidate(final Identifier identifier, final DataTreeCandidate foreign) + throws DataValidationFailedException { + LOG.debug("{}: Applying foreign transaction {}", logContext, identifier); + + final DataTreeModification mod = dataTree.takeSnapshot().newModification(); + DataTreeCandidates.applyToModification(mod, foreign); + mod.ready(); + + LOG.trace("{}: Applying foreign modification {}", logContext, mod); + dataTree.validate(mod); + final DataTreeCandidate candidate = dataTree.prepare(mod); + dataTree.commit(candidate); + + notifyListeners(candidate); + } + + /** + * Apply a payload coming from the leader, which could actually be us. This method assumes the leader and follower + * SchemaContexts match and does not perform any pruning. + * + * @param identifier Payload identifier as returned from RaftActor + * @param payload Payload + * @throws IOException when the snapshot fails to deserialize + * @throws DataValidationFailedException when the snapshot fails to apply + */ + void applyReplicatedPayload(final Identifier identifier, final Payload payload) throws IOException, + DataValidationFailedException { + /* + * 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 + * if we are the leader and it has originated with us. + * + * The identifier will only ever be non-null when we were the leader which achieved consensus. Unfortunately, + * though, this may not be the case anymore, as we are being called some time afterwards and we may not be + * acting in that capacity anymore. + * + * In any case, we know that this is an entry coming from replication, hence we can be sure we will not observe + * pre-Boron state -- which limits the number of options here. + */ + if (payload instanceof CommitTransactionPayload) { + if (identifier == null) { + final Entry e = + ((CommitTransactionPayload) payload).getCandidate(); + applyReplicatedCandidate(e.getKey(), e.getValue()); + allMetadataCommittedTransaction(e.getKey()); + } else { + Verify.verify(identifier instanceof TransactionIdentifier); + payloadReplicationComplete((TransactionIdentifier) identifier); + } + } else { + LOG.warn("{}: ignoring unhandled identifier {} payload {}", logContext, identifier, payload); + } + } + + private void payloadReplicationComplete(final TransactionIdentifier txId) { + final CommitEntry current = pendingFinishCommits.peek(); + if (current == null) { + LOG.warn("{}: No outstanding transactions, ignoring consensus on transaction {}", logContext, txId); + return; + } + + if (!current.cohort.getIdentifier().equals(txId)) { + LOG.debug("{}: Head of pendingFinishCommits queue is {}, ignoring consensus on transaction {}", logContext, + current.cohort.getIdentifier(), txId); + return; + } + + finishCommit(current.cohort); + } + + private void allMetadataCommittedTransaction(final TransactionIdentifier txId) { + for (ShardDataTreeMetadata m : metadata) { + m.onTransactionCommitted(txId); + } } - private ShardDataTreeTransactionChain ensureTransactionChain(final String chainId) { - ShardDataTreeTransactionChain chain = transactionChains.get(chainId); + ShardDataTreeTransactionChain ensureTransactionChain(final LocalHistoryIdentifier localHistoryIdentifier) { + ShardDataTreeTransactionChain chain = transactionChains.get(localHistoryIdentifier); if (chain == null) { - chain = new ShardDataTreeTransactionChain(chainId, this); - transactionChains.put(chainId, chain); + chain = new ShardDataTreeTransactionChain(localHistoryIdentifier, this); + transactionChains.put(localHistoryIdentifier, chain); } return chain; } - ReadOnlyShardDataTreeTransaction newReadOnlyTransaction(final String txId, final String chainId) { - if (Strings.isNullOrEmpty(chainId)) { + ReadOnlyShardDataTreeTransaction newReadOnlyTransaction(final TransactionIdentifier txId) { + if (txId.getHistoryId().getHistoryId() == 0) { return new ReadOnlyShardDataTreeTransaction(txId, dataTree.takeSnapshot()); } - return ensureTransactionChain(chainId).newReadOnlyTransaction(txId); + return ensureTransactionChain(txId.getHistoryId()).newReadOnlyTransaction(txId); } - ReadWriteShardDataTreeTransaction newReadWriteTransaction(final String txId, final String chainId) { - if (Strings.isNullOrEmpty(chainId)) { - return new ReadWriteShardDataTreeTransaction(this, txId, dataTree.takeSnapshot().newModification()); + ReadWriteShardDataTreeTransaction newReadWriteTransaction(final TransactionIdentifier txId) { + if (txId.getHistoryId().getHistoryId() == 0) { + return new ReadWriteShardDataTreeTransaction(ShardDataTree.this, txId, dataTree.takeSnapshot() + .newModification()); } - return ensureTransactionChain(chainId).newReadWriteTransaction(txId); + return ensureTransactionChain(txId.getHistoryId()).newReadWriteTransaction(txId); } - void notifyListeners(final DataTreeCandidate candidate) { - LOG.debug("Notifying listeners on candidate {}", candidate); + @VisibleForTesting + public void notifyListeners(final DataTreeCandidate candidate) { + treeChangeListenerPublisher.publishChanges(candidate, logContext); + dataChangeListenerPublisher.publishChanges(candidate, logContext); + } - // DataTreeChanges first, as they are more light-weight - treeChangePublisher.publishChanges(candidate); + void notifyOfInitialData(final DataChangeListenerRegistration>> listenerReg, final Optional currentState) { + if (currentState.isPresent()) { + ShardDataChangeListenerPublisher localPublisher = dataChangeListenerPublisher.newInstance(); + localPublisher.registerDataChangeListener(listenerReg.getPath(), listenerReg.getInstance(), + listenerReg.getScope()); + localPublisher.publishChanges(currentState.get(), logContext); + } + } - // DataChanges second, as they are heavier - ResolveDataChangeEventsTask.create(candidate, listenerTree).resolve(MANAGER); + void notifyOfInitialData(final YangInstanceIdentifier path, final DOMDataTreeChangeListener listener, + final Optional currentState) { + if (currentState.isPresent()) { + ShardDataTreeChangeListenerPublisher localPublisher = treeChangeListenerPublisher.newInstance(); + localPublisher.registerTreeChangeListener(path, listener); + localPublisher.publishChanges(currentState.get(), logContext); + } } void closeAllTransactionChains() { @@ -110,59 +455,42 @@ public final class ShardDataTree extends ShardDataTreeTransactionParent { transactionChains.clear(); } - void closeTransactionChain(final String transactionChainId) { + void closeTransactionChain(final LocalHistoryIdentifier transactionChainId) { final ShardDataTreeTransactionChain chain = transactionChains.remove(transactionChainId); if (chain != null) { chain.close(); } else { - LOG.debug("Closing non-existent transaction chain {}", transactionChainId); + LOG.debug("{}: Closing non-existent transaction chain {}", logContext, transactionChainId); } } - Entry>>, DOMImmutableDataChangeEvent> registerChangeListener( - final YangInstanceIdentifier path, - final AsyncDataChangeListener> listener, final DataChangeScope scope) { - final ListenerRegistration>> reg = - listenerTree.registerDataChangeListener(path, listener, scope); + Entry>>, + Optional> registerChangeListener(final YangInstanceIdentifier path, + final AsyncDataChangeListener> listener, + final DataChangeScope scope) { + DataChangeListenerRegistration>> reg = + dataChangeListenerPublisher.registerDataChangeListener(path, listener, scope); - final Optional> currentState = dataTree.takeSnapshot().readNode(path); - final DOMImmutableDataChangeEvent event; - if (currentState.isPresent()) { - final NormalizedNode data = currentState.get(); - event = DOMImmutableDataChangeEvent.builder(DataChangeScope.BASE).setAfter(data).addCreated(path, data).build(); - } else { - event = null; - } - - return new SimpleEntry<>(reg, event); + return new SimpleEntry<>(reg, readCurrentData()); } - Entry, DataTreeCandidate> registerTreeChangeListener(final YangInstanceIdentifier path, - final DOMDataTreeChangeListener listener) { - final ListenerRegistration reg = treeChangePublisher.registerTreeChangeListener(path, listener); - - final Optional> currentState = dataTree.takeSnapshot().readNode(path); - final DataTreeCandidate event; - if (currentState.isPresent()) { - event = DataTreeCandidates.fromNormalizedNode(path, currentState.get()); - } else { - event = null; - } - return new SimpleEntry<>(reg, event); + private Optional readCurrentData() { + final Optional> currentState = + dataTree.takeSnapshot().readNode(YangInstanceIdentifier.EMPTY); + return currentState.isPresent() ? Optional.of(DataTreeCandidates.fromNormalizedNode( + YangInstanceIdentifier.EMPTY, currentState.get())) : Optional.absent(); } - void applyForeignCandidate(final String identifier, final DataTreeCandidate foreign) throws DataValidationFailedException { - LOG.debug("Applying foreign transaction {}", identifier); + public Entry, Optional> + registerTreeChangeListener(final YangInstanceIdentifier path, final DOMDataTreeChangeListener listener) { + final ListenerRegistration reg = + treeChangeListenerPublisher.registerTreeChangeListener(path, listener); - final DataTreeModification mod = dataTree.takeSnapshot().newModification(); - DataTreeCandidates.applyToModification(mod, foreign); - mod.ready(); + return new SimpleEntry<>(reg, readCurrentData()); + } - LOG.trace("Applying foreign modification {}", mod); - dataTree.validate(mod); - final DataTreeCandidate candidate = dataTree.prepare(mod); - dataTree.commit(candidate); - notifyListeners(candidate); + int getQueueSize() { + return pendingTransactions.size() + pendingCommits.size() + pendingFinishCommits.size(); } @Override @@ -174,7 +502,463 @@ public final class ShardDataTree extends ShardDataTreeTransactionParent { ShardDataTreeCohort finishTransaction(final ReadWriteShardDataTreeTransaction transaction) { final DataTreeModification snapshot = transaction.getSnapshot(); snapshot.ready(); - return new SimpleShardDataTreeCohort(this, snapshot); + + return createReadyCohort(transaction.getIdentifier(), snapshot); + } + + public Optional> readNode(final YangInstanceIdentifier path) { + return dataTree.takeSnapshot().readNode(path); + } + + DataTreeSnapshot takeSnapshot() { + return dataTree.takeSnapshot(); + } + + @VisibleForTesting + public DataTreeModification newModification() { + return dataTree.takeSnapshot().newModification(); } + /** + * Commits a modification. + * + * @deprecated This method violates DataTree containment and will be removed. + */ + @VisibleForTesting + @Deprecated + public DataTreeCandidate commit(final DataTreeModification modification) throws DataValidationFailedException { + // Direct modification commit is a utility, which cannot be used while we have transactions in-flight + Preconditions.checkState(tip == dataTree, "Cannot modify data tree while transacgitons are pending"); + + modification.ready(); + dataTree.validate(modification); + DataTreeCandidate candidate = dataTree.prepare(modification); + dataTree.commit(candidate); + return candidate; + } + + public Collection getAndClearPendingTransactions() { + Collection ret = new ArrayList<>(getQueueSize()); + + for (CommitEntry entry: pendingFinishCommits) { + ret.add(entry.cohort); + } + + for (CommitEntry entry: pendingCommits) { + ret.add(entry.cohort); + } + + for (CommitEntry entry: pendingTransactions) { + ret.add(entry.cohort); + } + + pendingFinishCommits.clear(); + pendingCommits.clear(); + pendingTransactions.clear(); + tip = dataTree; + return ret; + } + + @SuppressWarnings("checkstyle:IllegalCatch") + private void processNextPendingTransaction() { + processNextPending(pendingTransactions, State.CAN_COMMIT_PENDING, entry -> { + final SimpleShardDataTreeCohort cohort = entry.cohort; + final DataTreeModification modification = cohort.getDataTreeModification(); + + LOG.debug("{}: Validating transaction {}", logContext, cohort.getIdentifier()); + Exception cause; + try { + tip.validate(modification); + LOG.debug("{}: Transaction {} validated", logContext, cohort.getIdentifier()); + cohort.successfulCanCommit(); + entry.lastAccess = shard.ticker().read(); + return; + } catch (ConflictingModificationAppliedException e) { + LOG.warn("{}: Store Tx {}: Conflicting modification for path {}.", logContext, cohort.getIdentifier(), + e.getPath()); + cause = new OptimisticLockFailedException("Optimistic lock failed.", e); + } catch (DataValidationFailedException e) { + LOG.warn("{}: Store Tx {}: Data validation failed for path {}.", logContext, cohort.getIdentifier(), + e.getPath(), e); + + // For debugging purposes, allow dumping of the modification. Coupled with the above + // precondition log, it should allow us to understand what went on. + LOG.debug("{}: Store Tx {}: modifications: {} tree: {}", cohort.getIdentifier(), modification, + dataTree); + cause = new TransactionCommitFailedException("Data did not pass validation.", e); + } catch (Exception e) { + LOG.warn("{}: Unexpected failure in validation phase", logContext, e); + cause = e; + } + + // Failure path: propagate the failure, remove the transaction from the queue and loop to the next one + pendingTransactions.poll().cohort.failedCanCommit(cause); + }); + } + + private void processNextPending() { + processNextPendingFinishCommit(); + processNextPendingCommit(); + processNextPendingTransaction(); + } + + private void processNextPending(Queue queue, State allowedState, Consumer processor) { + while (!queue.isEmpty()) { + final CommitEntry entry = queue.peek(); + final SimpleShardDataTreeCohort cohort = entry.cohort; + + if (cohort.isFailed()) { + LOG.debug("{}: Removing failed transaction {}", logContext, cohort.getIdentifier()); + queue.remove(); + continue; + } + + if (cohort.getState() == allowedState) { + processor.accept(entry); + } + + break; + } + + maybeRunOperationOnPendingTransactionsComplete(); + } + + private void processNextPendingCommit() { + processNextPending(pendingCommits, State.COMMIT_PENDING, + entry -> startCommit(entry.cohort, entry.cohort.getCandidate())); + } + + private void processNextPendingFinishCommit() { + processNextPending(pendingFinishCommits, State.FINISH_COMMIT_PENDING, + entry -> payloadReplicationComplete(entry.cohort.getIdentifier())); + } + + private boolean peekNextPendingCommit() { + final CommitEntry first = pendingCommits.peek(); + return first != null && first.cohort.getState() == State.COMMIT_PENDING; + } + + void startCanCommit(final SimpleShardDataTreeCohort cohort) { + final SimpleShardDataTreeCohort current = pendingTransactions.peek().cohort; + if (!cohort.equals(current)) { + LOG.debug("{}: Transaction {} scheduled for canCommit step", logContext, cohort.getIdentifier()); + return; + } + + processNextPendingTransaction(); + } + + private void failPreCommit(final Exception cause) { + shard.getShardMBean().incrementFailedTransactionsCount(); + pendingTransactions.poll().cohort.failedPreCommit(cause); + processNextPendingTransaction(); + } + + @SuppressWarnings("checkstyle:IllegalCatch") + void startPreCommit(final SimpleShardDataTreeCohort cohort) { + final CommitEntry entry = pendingTransactions.peek(); + Preconditions.checkState(entry != null, "Attempted to pre-commit of %s when no transactions pending", cohort); + + final SimpleShardDataTreeCohort current = entry.cohort; + Verify.verify(cohort.equals(current), "Attempted to pre-commit %s while %s is pending", cohort, current); + + LOG.debug("{}: Preparing transaction {}", logContext, current.getIdentifier()); + + final DataTreeCandidateTip candidate; + try { + candidate = tip.prepare(cohort.getDataTreeModification()); + cohort.userPreCommit(candidate); + } catch (ExecutionException | TimeoutException | RuntimeException e) { + failPreCommit(e); + return; + } + + // Set the tip of the data tree. + tip = Verify.verifyNotNull(candidate); + + entry.lastAccess = shard.ticker().read(); + + pendingTransactions.remove(); + pendingCommits.add(entry); + + LOG.debug("{}: Transaction {} prepared", logContext, current.getIdentifier()); + + cohort.successfulPreCommit(candidate); + + processNextPendingTransaction(); + } + + private void failCommit(final Exception cause) { + shard.getShardMBean().incrementFailedTransactionsCount(); + pendingFinishCommits.poll().cohort.failedCommit(cause); + processNextPending(); + } + + @SuppressWarnings("checkstyle:IllegalCatch") + private void finishCommit(final SimpleShardDataTreeCohort cohort) { + final TransactionIdentifier txId = cohort.getIdentifier(); + final DataTreeCandidate candidate = cohort.getCandidate(); + + LOG.debug("{}: Resuming commit of transaction {}", logContext, txId); + + if (tip == candidate) { + // All pending candidates have been committed, reset the tip to the data tree. + tip = dataTree; + } + + try { + dataTree.commit(candidate); + } catch (Exception e) { + LOG.error("{}: Failed to commit transaction {}", logContext, txId, e); + failCommit(e); + return; + } + + shard.getShardMBean().incrementCommittedTransactionCount(); + shard.getShardMBean().setLastCommittedTransactionTime(System.currentTimeMillis()); + + // FIXME: propagate journal index + pendingFinishCommits.poll().cohort.successfulCommit(UnsignedLong.ZERO); + + LOG.trace("{}: Transaction {} committed, proceeding to notify", logContext, txId); + notifyListeners(candidate); + + processNextPending(); + } + + void startCommit(final SimpleShardDataTreeCohort cohort, final DataTreeCandidate candidate) { + final CommitEntry entry = pendingCommits.peek(); + Preconditions.checkState(entry != null, "Attempted to start commit of %s when no transactions pending", cohort); + + final SimpleShardDataTreeCohort current = entry.cohort; + if (!cohort.equals(current)) { + LOG.debug("{}: Transaction {} scheduled for commit step", logContext, cohort.getIdentifier()); + return; + } + + LOG.debug("{}: Starting commit for transaction {}", logContext, current.getIdentifier()); + + final TransactionIdentifier txId = cohort.getIdentifier(); + if (shard.canSkipPayload() || candidate.getRootNode().getModificationType() == ModificationType.UNMODIFIED) { + LOG.debug("{}: No replication required, proceeding to finish commit", logContext); + pendingCommits.remove(); + pendingFinishCommits.add(entry); + cohort.finishCommitPending(); + payloadReplicationComplete(txId); + return; + } + + final Payload payload; + try { + payload = CommitTransactionPayload.create(txId, candidate); + } catch (IOException e) { + LOG.error("{}: Failed to encode transaction {} candidate {}", logContext, txId, candidate, e); + pendingCommits.poll().cohort.failedCommit(e); + processNextPending(); + return; + } + + // We process next transactions pending canCommit before we call persistPayload to possibly progress subsequent + // transactions to the COMMIT_PENDING state so the payloads can be batched for replication. This is done for + // single-shard transactions that immediately transition from canCommit to preCommit to commit. Note that + // if the next pending transaction is progressed to COMMIT_PENDING and this method (startCommit) is called, + // the next transaction will not attempt to replicate b/c the current transaction is still at the head of the + // pendingCommits queue. + processNextPendingTransaction(); + + // After processing next pending transactions, we can now remove the current transaction from pendingCommits. + // Note this must be done before the call to peekNextPendingCommit below so we check the next transaction + // in order to properly determine the batchHint flag for the call to persistPayload. + pendingCommits.remove(); + pendingFinishCommits.add(entry); + + // See if the next transaction is pending commit (ie in the COMMIT_PENDING state) so it can be batched with + // this transaction for replication. + boolean replicationBatchHint = peekNextPendingCommit(); + + // Once completed, we will continue via payloadReplicationComplete + shard.persistPayload(txId, payload, replicationBatchHint); + + entry.lastAccess = shard.ticker().read(); + + LOG.debug("{}: Transaction {} submitted to persistence", logContext, txId); + + // Process the next transaction pending commit, if any. If there is one it will be batched with this + // transaction for replication. + processNextPendingCommit(); + } + + void processCohortRegistryCommand(final ActorRef sender, final CohortRegistryCommand message) { + cohortRegistry.process(sender, message); + } + + @Override + ShardDataTreeCohort createReadyCohort(final TransactionIdentifier txId, + final DataTreeModification modification) { + SimpleShardDataTreeCohort cohort = new SimpleShardDataTreeCohort(this, modification, txId, + cohortRegistry.createCohort(schemaContext, txId, COMMIT_STEP_TIMEOUT)); + pendingTransactions.add(new CommitEntry(cohort, shard.ticker().read())); + return cohort; + } + + @SuppressFBWarnings(value = "DB_DUPLICATE_SWITCH_CLAUSES", justification = "See inline comments below.") + void checkForExpiredTransactions(final long transactionCommitTimeoutMillis) { + final long timeout = TimeUnit.MILLISECONDS.toNanos(transactionCommitTimeoutMillis); + final long now = shard.ticker().read(); + + final Queue currentQueue = !pendingFinishCommits.isEmpty() ? pendingFinishCommits : + !pendingCommits.isEmpty() ? pendingCommits : pendingTransactions; + final CommitEntry currentTx = currentQueue.peek(); + if (currentTx != null && currentTx.lastAccess + timeout < now) { + LOG.warn("{}: Current transaction {} has timed out after {} ms in state {}", logContext, + currentTx.cohort.getIdentifier(), transactionCommitTimeoutMillis, currentTx.cohort.getState()); + boolean processNext = true; + switch (currentTx.cohort.getState()) { + case CAN_COMMIT_PENDING: + currentQueue.remove().cohort.failedCanCommit(new TimeoutException()); + break; + case CAN_COMMIT_COMPLETE: + // The suppression of the FindBugs "DB_DUPLICATE_SWITCH_CLAUSES" warning pertains to this clause + // whose code is duplicated with PRE_COMMIT_COMPLETE. The clauses aren't combined in case the code + // in PRE_COMMIT_COMPLETE is changed. + currentQueue.remove().cohort.reportFailure(new TimeoutException()); + break; + case PRE_COMMIT_PENDING: + currentQueue.remove().cohort.failedPreCommit(new TimeoutException()); + break; + case PRE_COMMIT_COMPLETE: + // FIXME: this is a legacy behavior problem. Three-phase commit protocol specifies that after we + // are ready we should commit the transaction, not abort it. Our current software stack does + // not allow us to do that consistently, because we persist at the time of commit, hence + // we can end up in a state where we have pre-committed a transaction, then a leader failover + // occurred ... the new leader does not see the pre-committed transaction and does not have + // a running timer. To fix this we really need two persistence events. + // + // The first one, done at pre-commit time will hold the transaction payload. When consensus + // is reached, we exit the pre-commit phase and start the pre-commit timer. Followers do not + // apply the state in this event. + // + // The second one, done at commit (or abort) time holds only the transaction identifier and + // signals to followers that the state should (or should not) be applied. + // + // In order to make the pre-commit timer working across failovers, though, we need + // a per-shard cluster-wide monotonic time, so a follower becoming the leader can accurately + // restart the timer. + currentQueue.remove().cohort.reportFailure(new TimeoutException()); + break; + case COMMIT_PENDING: + LOG.warn("{}: Transaction {} is still committing, cannot abort", logContext, + currentTx.cohort.getIdentifier()); + currentTx.lastAccess = now; + processNext = false; + return; + case ABORTED: + case COMMITTED: + case FAILED: + case READY: + default: + currentQueue.remove(); + } + + if (processNext) { + processNextPending(); + } + } + } + + boolean startAbort(final SimpleShardDataTreeCohort cohort) { + final Iterator it = Iterables.concat(pendingFinishCommits, pendingCommits, + pendingTransactions).iterator(); + if (!it.hasNext()) { + LOG.debug("{}: no open transaction while attempting to abort {}", logContext, cohort.getIdentifier()); + return true; + } + + // First entry is special, as it may already be committing + final CommitEntry first = it.next(); + if (cohort.equals(first.cohort)) { + if (cohort.getState() != State.COMMIT_PENDING) { + LOG.debug("{}: aborting head of queue {} in state {}", logContext, cohort.getIdentifier(), + cohort.getIdentifier()); + + it.remove(); + if (cohort.getCandidate() != null) { + rebaseTransactions(it, dataTree); + } + + processNextPending(); + return true; + } + + LOG.warn("{}: transaction {} is committing, skipping abort", logContext, cohort.getIdentifier()); + return false; + } + + TipProducingDataTreeTip newTip = MoreObjects.firstNonNull(first.cohort.getCandidate(), dataTree); + while (it.hasNext()) { + final CommitEntry e = it.next(); + if (cohort.equals(e.cohort)) { + LOG.debug("{}: aborting queued transaction {}", logContext, cohort.getIdentifier()); + + it.remove(); + if (cohort.getCandidate() != null) { + rebaseTransactions(it, newTip); + } + + return true; + } else { + newTip = MoreObjects.firstNonNull(e.cohort.getCandidate(), newTip); + } + } + + LOG.debug("{}: aborted transaction {} not found in the queue", logContext, cohort.getIdentifier()); + return true; + } + + @SuppressWarnings("checkstyle:IllegalCatch") + private void rebaseTransactions(Iterator iter, @Nonnull TipProducingDataTreeTip newTip) { + tip = Preconditions.checkNotNull(newTip); + while (iter.hasNext()) { + final SimpleShardDataTreeCohort cohort = iter.next().cohort; + if (cohort.getState() == State.CAN_COMMIT_COMPLETE) { + LOG.debug("{}: Revalidating queued transaction {}", logContext, cohort.getIdentifier()); + + try { + tip.validate(cohort.getDataTreeModification()); + } catch (DataValidationFailedException | RuntimeException e) { + LOG.debug("{}: Failed to revalidate queued transaction {}", logContext, cohort.getIdentifier(), e); + cohort.reportFailure(e); + } + } else if (cohort.getState() == State.PRE_COMMIT_COMPLETE) { + LOG.debug("{}: Repreparing queued transaction {}", logContext, cohort.getIdentifier()); + + try { + tip.validate(cohort.getDataTreeModification()); + DataTreeCandidateTip candidate = tip.prepare(cohort.getDataTreeModification()); + cohort.userPreCommit(candidate); + + cohort.setNewCandidate(candidate); + tip = candidate; + } catch (ExecutionException | TimeoutException | RuntimeException | DataValidationFailedException e) { + LOG.debug("{}: Failed to reprepare queued transaction {}", logContext, cohort.getIdentifier(), e); + cohort.reportFailure(e); + } + } + } + } + + void setRunOnPendingTransactionsComplete(final Runnable operation) { + runOnPendingTransactionsComplete = operation; + maybeRunOperationOnPendingTransactionsComplete(); + } + + private void maybeRunOperationOnPendingTransactionsComplete() { + if (runOnPendingTransactionsComplete != null && !anyPendingTransactions()) { + LOG.debug("{}: Pending transactions complete - running operation {}", logContext, + runOnPendingTransactionsComplete); + + runOnPendingTransactionsComplete.run(); + runOnPendingTransactionsComplete = null; + } + } }