2 * Copyright (c) 2014 Brocade Communications 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.databroker;
10 import com.google.common.annotations.Beta;
11 import com.google.common.base.Preconditions;
12 import com.google.common.util.concurrent.AbstractFuture;
13 import com.google.common.util.concurrent.CheckedFuture;
14 import com.google.common.util.concurrent.FutureCallback;
15 import com.google.common.util.concurrent.Futures;
16 import com.google.common.util.concurrent.ListenableFuture;
17 import com.google.common.util.concurrent.MoreExecutors;
18 import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
19 import java.util.Collection;
20 import java.util.Iterator;
21 import java.util.List;
23 import java.util.concurrent.Executor;
24 import org.opendaylight.controller.cluster.datastore.exceptions.NoShardLeaderException;
25 import org.opendaylight.controller.cluster.datastore.exceptions.ShardLeaderNotRespondingException;
26 import org.opendaylight.controller.md.sal.common.api.data.DataStoreUnavailableException;
27 import org.opendaylight.controller.md.sal.common.api.data.LogicalDatastoreType;
28 import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFailedException;
29 import org.opendaylight.controller.md.sal.dom.api.DOMDataWriteTransaction;
30 import org.opendaylight.controller.md.sal.dom.broker.impl.TransactionCommitFailedExceptionMapper;
31 import org.opendaylight.controller.sal.core.spi.data.DOMStore;
32 import org.opendaylight.controller.sal.core.spi.data.DOMStoreThreePhaseCommitCohort;
33 import org.opendaylight.yangtools.util.DurationStatisticsTracker;
34 import org.opendaylight.yangtools.util.concurrent.MappingCheckedFuture;
35 import org.slf4j.Logger;
36 import org.slf4j.LoggerFactory;
39 * ConcurrentDOMDataBroker commits transactions concurrently. The 3
40 * commit phases (canCommit, preCommit, and commit) are performed serially and non-blocking
41 * (ie async) per transaction but multiple transaction commits can run concurrent.
43 * @author Thomas Pantelis
46 public class ConcurrentDOMDataBroker extends AbstractDOMBroker {
47 private static final Logger LOG = LoggerFactory.getLogger(ConcurrentDOMDataBroker.class);
48 private static final String CAN_COMMIT = "CAN_COMMIT";
49 private static final String PRE_COMMIT = "PRE_COMMIT";
50 private static final String COMMIT = "COMMIT";
52 private final DurationStatisticsTracker commitStatsTracker;
55 * This executor is used to execute Future listener callback Runnables async.
57 private final Executor clientFutureCallbackExecutor;
59 public ConcurrentDOMDataBroker(final Map<LogicalDatastoreType, DOMStore> datastores,
60 Executor listenableFutureExecutor) {
61 this(datastores, listenableFutureExecutor, DurationStatisticsTracker.createConcurrent());
64 public ConcurrentDOMDataBroker(final Map<LogicalDatastoreType, DOMStore> datastores,
65 Executor listenableFutureExecutor, DurationStatisticsTracker commitStatsTracker) {
67 this.clientFutureCallbackExecutor = Preconditions.checkNotNull(listenableFutureExecutor);
68 this.commitStatsTracker = Preconditions.checkNotNull(commitStatsTracker);
71 public DurationStatisticsTracker getCommitStatsTracker() {
72 return commitStatsTracker;
76 protected CheckedFuture<Void, TransactionCommitFailedException> submit(DOMDataWriteTransaction transaction,
77 Collection<DOMStoreThreePhaseCommitCohort> cohorts) {
79 Preconditions.checkArgument(transaction != null, "Transaction must not be null.");
80 Preconditions.checkArgument(cohorts != null, "Cohorts must not be null.");
81 LOG.debug("Tx: {} is submitted for execution.", transaction.getIdentifier());
83 if (cohorts.isEmpty()) {
84 return Futures.immediateCheckedFuture(null);
87 final AsyncNotifyingSettableFuture clientSubmitFuture =
88 new AsyncNotifyingSettableFuture(clientFutureCallbackExecutor);
90 doCanCommit(clientSubmitFuture, transaction, cohorts);
92 return MappingCheckedFuture.create(clientSubmitFuture,
93 TransactionCommitFailedExceptionMapper.COMMIT_ERROR_MAPPER);
96 private void doCanCommit(final AsyncNotifyingSettableFuture clientSubmitFuture,
97 final DOMDataWriteTransaction transaction,
98 final Collection<DOMStoreThreePhaseCommitCohort> cohorts) {
100 final long startTime = System.nanoTime();
102 final Iterator<DOMStoreThreePhaseCommitCohort> cohortIterator = cohorts.iterator();
104 // Not using Futures.allAsList here to avoid its internal overhead.
105 FutureCallback<Boolean> futureCallback = new FutureCallback<Boolean>() {
107 public void onSuccess(Boolean result) {
108 if (result == null || !result) {
109 handleException(clientSubmitFuture, transaction, cohorts,
110 CAN_COMMIT, TransactionCommitFailedExceptionMapper.CAN_COMMIT_ERROR_MAPPER,
111 new TransactionCommitFailedException(
112 "Can Commit failed, no detailed cause available."));
114 if (!cohortIterator.hasNext()) {
115 // All cohorts completed successfully - we can move on to the preCommit phase
116 doPreCommit(startTime, clientSubmitFuture, transaction, cohorts);
118 ListenableFuture<Boolean> canCommitFuture = cohortIterator.next().canCommit();
119 Futures.addCallback(canCommitFuture, this, MoreExecutors.directExecutor());
125 public void onFailure(Throwable failure) {
126 handleException(clientSubmitFuture, transaction, cohorts, CAN_COMMIT,
127 TransactionCommitFailedExceptionMapper.CAN_COMMIT_ERROR_MAPPER, failure);
131 ListenableFuture<Boolean> canCommitFuture = cohortIterator.next().canCommit();
132 Futures.addCallback(canCommitFuture, futureCallback, MoreExecutors.directExecutor());
135 private void doPreCommit(final long startTime, final AsyncNotifyingSettableFuture clientSubmitFuture,
136 final DOMDataWriteTransaction transaction,
137 final Collection<DOMStoreThreePhaseCommitCohort> cohorts) {
139 final Iterator<DOMStoreThreePhaseCommitCohort> cohortIterator = cohorts.iterator();
141 // Not using Futures.allAsList here to avoid its internal overhead.
142 FutureCallback<Void> futureCallback = new FutureCallback<Void>() {
144 public void onSuccess(Void notUsed) {
145 if (!cohortIterator.hasNext()) {
146 // All cohorts completed successfully - we can move on to the commit phase
147 doCommit(startTime, clientSubmitFuture, transaction, cohorts);
149 ListenableFuture<Void> preCommitFuture = cohortIterator.next().preCommit();
150 Futures.addCallback(preCommitFuture, this, MoreExecutors.directExecutor());
155 public void onFailure(Throwable failure) {
156 handleException(clientSubmitFuture, transaction, cohorts, PRE_COMMIT,
157 TransactionCommitFailedExceptionMapper.PRE_COMMIT_MAPPER, failure);
161 ListenableFuture<Void> preCommitFuture = cohortIterator.next().preCommit();
162 Futures.addCallback(preCommitFuture, futureCallback, MoreExecutors.directExecutor());
165 private void doCommit(final long startTime, final AsyncNotifyingSettableFuture clientSubmitFuture,
166 final DOMDataWriteTransaction transaction,
167 final Collection<DOMStoreThreePhaseCommitCohort> cohorts) {
169 final Iterator<DOMStoreThreePhaseCommitCohort> cohortIterator = cohorts.iterator();
171 // Not using Futures.allAsList here to avoid its internal overhead.
172 FutureCallback<Void> futureCallback = new FutureCallback<Void>() {
174 public void onSuccess(Void notUsed) {
175 if (!cohortIterator.hasNext()) {
176 // All cohorts completed successfully - we're done.
177 commitStatsTracker.addDuration(System.nanoTime() - startTime);
179 clientSubmitFuture.set();
181 ListenableFuture<Void> commitFuture = cohortIterator.next().commit();
182 Futures.addCallback(commitFuture, this, MoreExecutors.directExecutor());
187 public void onFailure(Throwable throwable) {
188 handleException(clientSubmitFuture, transaction, cohorts, COMMIT,
189 TransactionCommitFailedExceptionMapper.COMMIT_ERROR_MAPPER, throwable);
193 ListenableFuture<Void> commitFuture = cohortIterator.next().commit();
194 Futures.addCallback(commitFuture, futureCallback, MoreExecutors.directExecutor());
197 @SuppressFBWarnings(value = "BC_UNCONFIRMED_CAST_OF_RETURN_VALUE",
198 justification = "Pertains to the assignment of the 'clientException' var. FindBugs flags this as an "
199 + "uncomfirmed cast but the generic type in TransactionCommitFailedExceptionMapper is "
200 + "TransactionCommitFailedException and thus should be deemed as confirmed.")
201 private static void handleException(final AsyncNotifyingSettableFuture clientSubmitFuture,
202 final DOMDataWriteTransaction transaction,
203 final Collection<DOMStoreThreePhaseCommitCohort> cohorts,
204 final String phase, final TransactionCommitFailedExceptionMapper exMapper,
205 final Throwable throwable) {
207 if (clientSubmitFuture.isDone()) {
208 // We must have had failures from multiple cohorts.
212 LOG.warn("Tx: {} Error during phase {}, starting Abort", transaction.getIdentifier(), phase, throwable);
214 if (throwable instanceof NoShardLeaderException || throwable instanceof ShardLeaderNotRespondingException) {
215 e = new DataStoreUnavailableException(throwable.getMessage(), throwable);
216 } else if (throwable instanceof Exception) {
217 e = (Exception)throwable;
219 e = new RuntimeException("Unexpected error occurred", throwable);
222 final TransactionCommitFailedException clientException = exMapper.apply(e);
224 // Transaction failed - tell all cohorts to abort.
226 @SuppressWarnings("unchecked")
227 ListenableFuture<Void>[] canCommitFutures = new ListenableFuture[cohorts.size()];
229 for (DOMStoreThreePhaseCommitCohort cohort : cohorts) {
230 canCommitFutures[index++] = cohort.abort();
233 ListenableFuture<List<Void>> combinedFuture = Futures.allAsList(canCommitFutures);
234 Futures.addCallback(combinedFuture, new FutureCallback<List<Void>>() {
236 public void onSuccess(List<Void> notUsed) {
237 // Propagate the original exception to the client.
238 clientSubmitFuture.setException(clientException);
242 public void onFailure(Throwable failure) {
243 LOG.error("Tx: {} Error during Abort.", transaction.getIdentifier(), failure);
245 // Propagate the original exception as that is what caused the Tx to fail and is
246 // what's interesting to the client.
247 clientSubmitFuture.setException(clientException);
249 }, MoreExecutors.directExecutor());
253 * A settable future that uses an {@link Executor} to execute listener callback Runnables,
254 * registered via {@link #addListener}, asynchronously when this future completes. This is
255 * done to guarantee listener executions are off-loaded onto another thread to avoid blocking
256 * the thread that completed this future, as a common use case is to pass an executor that runs
257 * tasks in the same thread as the caller (ie MoreExecutors#sameThreadExecutor)
258 * to {@link #addListener}.
259 * FIXME: This class should probably be moved to yangtools common utils for re-usability and
260 * unified with AsyncNotifyingListenableFutureTask.
262 private static class AsyncNotifyingSettableFuture extends AbstractFuture<Void> {
265 * ThreadLocal used to detect if the task completion thread is running the future listener Runnables.
267 private static final ThreadLocal<Boolean> ON_TASK_COMPLETION_THREAD_TL = new ThreadLocal<>();
269 private final Executor listenerExecutor;
271 AsyncNotifyingSettableFuture(Executor listenerExecutor) {
272 this.listenerExecutor = Preconditions.checkNotNull(listenerExecutor);
276 public void addListener(final Runnable listener, final Executor executor) {
277 // Wrap the listener Runnable in a DelegatingRunnable. If the specified executor is one
278 // that runs tasks in the same thread as the caller submitting the task
279 // (e.g. {@link com.google.common.util.concurrent.MoreExecutors#sameThreadExecutor}) and
280 // the listener is executed from the #set methods, then the DelegatingRunnable will detect
281 // this via the ThreadLocal and submit the listener Runnable to the listenerExecutor.
283 // On the other hand, if this task is already complete, the call to ExecutionList#add in
284 // superclass will execute the listener Runnable immediately and, since the ThreadLocal
285 // won't be set, the DelegatingRunnable will run the listener Runnable inline.
286 super.addListener(new DelegatingRunnable(listener, listenerExecutor), executor);
290 ON_TASK_COMPLETION_THREAD_TL.set(Boolean.TRUE);
292 return super.set(null);
294 ON_TASK_COMPLETION_THREAD_TL.set(null);
299 protected boolean setException(Throwable throwable) {
300 ON_TASK_COMPLETION_THREAD_TL.set(Boolean.TRUE);
302 return super.setException(throwable);
304 ON_TASK_COMPLETION_THREAD_TL.set(null);
308 private static final class DelegatingRunnable implements Runnable {
309 private final Runnable delegate;
310 private final Executor executor;
312 DelegatingRunnable(final Runnable delegate, final Executor executor) {
313 this.delegate = Preconditions.checkNotNull(delegate);
314 this.executor = Preconditions.checkNotNull(executor);
319 if (ON_TASK_COMPLETION_THREAD_TL.get() != null) {
320 // We're running on the task completion thread so off-load to the executor.
321 LOG.trace("Submitting ListenenableFuture Runnable from thread {} to executor {}",
322 Thread.currentThread().getName(), executor);
323 executor.execute(delegate);
325 // We're not running on the task completion thread so run the delegate inline.
326 LOG.trace("Executing ListenenableFuture Runnable on this thread: {}",
327 Thread.currentThread().getName());
335 public String toString() {
336 return "Clustered ConcurrentDOMDataBroker";