opendaylight/md-sal/sal-akka-segmented-journal/src/main/java/org/opendaylight/controller/akka/segjournal/SegmentedJournalActor.java

   1 /*
   2  * Copyright (c) 2019 Pantheon Technologies, s.r.o. and others.  All rights reserved.
   3  *
   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
   7  */
   8 package org.opendaylight.controller.akka.segjournal;
   9
  10 import static com.google.common.base.Verify.verify;
  11 import static com.google.common.base.Verify.verifyNotNull;
  12 import static java.util.Objects.requireNonNull;
  13
  14 import akka.actor.AbstractActor;
  15 import akka.actor.Props;
  16 import akka.persistence.AtomicWrite;
  17 import akka.persistence.PersistentRepr;
  18 import com.codahale.metrics.Histogram;
  19 import com.codahale.metrics.Meter;
  20 import com.codahale.metrics.MetricRegistry;
  21 import com.codahale.metrics.Timer;
  22 import com.google.common.base.MoreObjects;
  23 import io.atomix.storage.StorageLevel;
  24 import io.atomix.storage.journal.Indexed;
  25 import io.atomix.storage.journal.SegmentedJournal;
  26 import io.atomix.storage.journal.SegmentedJournalReader;
  27 import io.atomix.storage.journal.SegmentedJournalWriter;
  28 import io.atomix.utils.serializer.Namespace;
  29 import java.io.File;
  30 import java.io.Serializable;
  31 import java.util.ArrayList;
  32 import java.util.List;
  33 import java.util.Optional;
  34 import java.util.concurrent.TimeUnit;
  35 import java.util.function.Consumer;
  36 import org.opendaylight.controller.akka.segjournal.DataJournalEntry.FromPersistence;
  37 import org.opendaylight.controller.akka.segjournal.DataJournalEntry.ToPersistence;
  38 import org.opendaylight.controller.cluster.common.actor.MeteringBehavior;
  39 import org.opendaylight.controller.cluster.reporting.MetricsReporter;
  40 import org.slf4j.Logger;
  41 import org.slf4j.LoggerFactory;
  42 import scala.concurrent.Future;
  43 import scala.concurrent.Promise;
  44 import scala.jdk.javaapi.CollectionConverters;
  45
  46 /**
  47  * This actor handles a single PersistentActor's journal. The journal is split into two {@link SegmentedJournal}s:
  48  * <ul>
  49  *     <li>A memory-mapped data journal, containing actual data entries</li>
  50  *     <li>A simple file journal, containing sequence numbers of last deleted entry</li>
  51  * </ul>
  52  *
  53  * <p>
  54  * This is a conscious design decision to minimize the amount of data that is being stored in the data journal while
  55  * speeding up normal operations. Since the SegmentedJournal is an append-only linear log and Akka requires the ability
  56  * to delete persistence entries, we need ability to mark a subset of a SegmentedJournal as deleted. While we could
  57  * treat such delete requests as normal events, this leads to a mismatch between SegmentedJournal indices (as exposed by
  58  * {@link Indexed}) and Akka sequence numbers -- requiring us to potentially perform costly deserialization to find the
  59  * index corresponding to a particular sequence number, or maintain moderately-complex logic and data structures to
  60  * perform that mapping in sub-linear time complexity.
  61  *
  62  * <p>
  63  * Split-file approach allows us to treat sequence numbers and indices as equivalent, without maintaining any explicit
  64  * mapping information. The only additional information we need to maintain is the last deleted sequence number.
  65  *
  66  * @author Robert Varga
  67  */
  68 final class SegmentedJournalActor extends AbstractActor {
  69     abstract static class AsyncMessage<T> {
  70         final Promise<T> promise = Promise.apply();
  71     }
  72
  73     private static final class ReadHighestSequenceNr extends AsyncMessage<Long> {
  74         private final long fromSequenceNr;
  75
  76         ReadHighestSequenceNr(final long fromSequenceNr) {
  77             this.fromSequenceNr = fromSequenceNr;
  78         }
  79
  80         @Override
  81         public String toString() {
  82             return MoreObjects.toStringHelper(this).add("fromSequenceNr", fromSequenceNr).toString();
  83         }
  84     }
  85
  86     private static final class ReplayMessages extends AsyncMessage<Void> {
  87         private final long fromSequenceNr;
  88         private final long toSequenceNr;
  89         private final long max;
  90         private final Consumer<PersistentRepr> replayCallback;
  91
  92         ReplayMessages(final long fromSequenceNr,
  93                 final long toSequenceNr, final long max, final Consumer<PersistentRepr> replayCallback) {
  94             this.fromSequenceNr = fromSequenceNr;
  95             this.toSequenceNr = toSequenceNr;
  96             this.max = max;
  97             this.replayCallback = requireNonNull(replayCallback);
  98         }
  99
 100         @Override
 101         public String toString() {
 102             return MoreObjects.toStringHelper(this).add("fromSequenceNr", fromSequenceNr)
 103                     .add("toSequenceNr", toSequenceNr).add("max", max).toString();
 104         }
 105     }
 106
 107     static final class WriteMessages {
 108         private final List<AtomicWrite> requests = new ArrayList<>();
 109         private final List<Promise<Optional<Exception>>> results = new ArrayList<>();
 110
 111         Future<Optional<Exception>> add(final AtomicWrite write) {
 112             final Promise<Optional<Exception>> promise = Promise.apply();
 113             requests.add(write);
 114             results.add(promise);
 115             return promise.future();
 116         }
 117
 118         @Override
 119         public String toString() {
 120             return MoreObjects.toStringHelper(this).add("requests", requests).toString();
 121         }
 122     }
 123
 124     private static final class DeleteMessagesTo extends AsyncMessage<Void> {
 125         final long toSequenceNr;
 126
 127         DeleteMessagesTo(final long toSequenceNr) {
 128             this.toSequenceNr = toSequenceNr;
 129         }
 130
 131         @Override
 132         public String toString() {
 133             return MoreObjects.toStringHelper(this).add("toSequenceNr", toSequenceNr).toString();
 134         }
 135     }
 136
 137     private static final Logger LOG = LoggerFactory.getLogger(SegmentedJournalActor.class);
 138     private static final Namespace DELETE_NAMESPACE = Namespace.builder().register(Long.class).build();
 139     private static final int DELETE_SEGMENT_SIZE = 64 * 1024;
 140
 141     private final String persistenceId;
 142     private final StorageLevel storage;
 143     private final int maxSegmentSize;
 144     private final int maxEntrySize;
 145     private final File directory;
 146
 147     // Tracks the time it took us to write a batch of messages
 148     private Timer batchWriteTime;
 149     // Tracks the number of individual messages written
 150     private Meter messageWriteCount;
 151     // Tracks the size distribution of messages
 152     private Histogram messageSize;
 153
 154     private SegmentedJournal<DataJournalEntry> dataJournal;
 155     private SegmentedJournal<Long> deleteJournal;
 156     private long lastDelete;
 157
 158     // Tracks largest message size we have observed either during recovery or during write
 159     private int largestObservedSize;
 160
 161     SegmentedJournalActor(final String persistenceId, final File directory, final StorageLevel storage,
 162             final int maxEntrySize, final int maxSegmentSize) {
 163         this.persistenceId = requireNonNull(persistenceId);
 164         this.directory = requireNonNull(directory);
 165         this.storage = requireNonNull(storage);
 166         this.maxEntrySize = maxEntrySize;
 167         this.maxSegmentSize = maxSegmentSize;
 168     }
 169
 170     static Props props(final String persistenceId, final File directory, final StorageLevel storage,
 171             final int maxEntrySize, final int maxSegmentSize) {
 172         return Props.create(SegmentedJournalActor.class, requireNonNull(persistenceId), directory, storage,
 173             maxEntrySize, maxSegmentSize);
 174     }
 175
 176     @Override
 177     public Receive createReceive() {
 178         return receiveBuilder()
 179                 .match(DeleteMessagesTo.class, this::handleDeleteMessagesTo)
 180                 .match(ReadHighestSequenceNr.class, this::handleReadHighestSequenceNr)
 181                 .match(ReplayMessages.class, this::handleReplayMessages)
 182                 .match(WriteMessages.class, this::handleWriteMessages)
 183                 .matchAny(this::handleUnknown)
 184                 .build();
 185     }
 186
 187     @Override
 188     public void preStart() throws Exception {
 189         LOG.debug("{}: actor starting", persistenceId);
 190         super.preStart();
 191
 192         final MetricRegistry registry = MetricsReporter.getInstance(MeteringBehavior.DOMAIN).getMetricsRegistry();
 193         final String actorName = self().path().parent().toStringWithoutAddress() + '/' + directory.getName();
 194
 195         batchWriteTime = registry.timer(MetricRegistry.name(actorName, "batchWriteTime"));
 196         messageWriteCount = registry.meter(MetricRegistry.name(actorName, "messageWriteCount"));
 197         messageSize = registry.histogram(MetricRegistry.name(actorName, "messageSize"));
 198     }
 199
 200     @Override
 201     public void postStop() throws Exception {
 202         LOG.debug("{}: actor stopping", persistenceId);
 203         if (dataJournal != null) {
 204             dataJournal.close();
 205             LOG.debug("{}: data journal closed", persistenceId);
 206             dataJournal = null;
 207         }
 208         if (deleteJournal != null) {
 209             deleteJournal.close();
 210             LOG.debug("{}: delete journal closed", persistenceId);
 211             deleteJournal = null;
 212         }
 213         LOG.debug("{}: actor stopped", persistenceId);
 214         super.postStop();
 215     }
 216
 217     static AsyncMessage<Void> deleteMessagesTo(final long toSequenceNr) {
 218         return new DeleteMessagesTo(toSequenceNr);
 219     }
 220
 221     static AsyncMessage<Long> readHighestSequenceNr(final long fromSequenceNr) {
 222         return new ReadHighestSequenceNr(fromSequenceNr);
 223     }
 224
 225     static AsyncMessage<Void> replayMessages(final long fromSequenceNr, final long toSequenceNr, final long max,
 226             final Consumer<PersistentRepr> replayCallback) {
 227         return new ReplayMessages(fromSequenceNr, toSequenceNr, max, replayCallback);
 228     }
 229
 230     private void handleDeleteMessagesTo(final DeleteMessagesTo message) {
 231         ensureOpen();
 232
 233         LOG.debug("{}: delete messages {}", persistenceId, message);
 234         final long to = Long.min(dataJournal.writer().getLastIndex(), message.toSequenceNr);
 235         LOG.debug("{}: adjusted delete to {}", persistenceId, to);
 236
 237         if (lastDelete < to) {
 238             LOG.debug("{}: deleting entries up to {}", persistenceId, to);
 239
 240             lastDelete = to;
 241             final SegmentedJournalWriter<Long> deleteWriter = deleteJournal.writer();
 242             final Indexed<Long> entry = deleteWriter.append(lastDelete);
 243             deleteWriter.commit(entry.index());
 244             dataJournal.writer().commit(lastDelete);
 245
 246             LOG.debug("{}: compaction started", persistenceId);
 247             dataJournal.compact(lastDelete + 1);
 248             deleteJournal.compact(entry.index());
 249             LOG.debug("{}: compaction finished", persistenceId);
 250         } else {
 251             LOG.debug("{}: entries up to {} already deleted", persistenceId, lastDelete);
 252         }
 253
 254         message.promise.success(null);
 255     }
 256
 257     private void handleReadHighestSequenceNr(final ReadHighestSequenceNr message) {
 258         LOG.debug("{}: looking for highest sequence on {}", persistenceId, message);
 259         final Long sequence;
 260         if (directory.isDirectory()) {
 261             ensureOpen();
 262             sequence = dataJournal.writer().getLastIndex();
 263         } else {
 264             sequence = 0L;
 265         }
 266
 267         LOG.debug("{}: highest sequence is {}", message, sequence);
 268         message.promise.success(sequence);
 269     }
 270
 271     @SuppressWarnings("checkstyle:illegalCatch")
 272     private void handleReplayMessages(final ReplayMessages message) {
 273         LOG.debug("{}: replaying messages {}", persistenceId, message);
 274         ensureOpen();
 275
 276         final long from = Long.max(lastDelete + 1, message.fromSequenceNr);
 277         LOG.debug("{}: adjusted fromSequenceNr to {}", persistenceId, from);
 278
 279         try (SegmentedJournalReader<DataJournalEntry> reader = dataJournal.openReader(from)) {
 280             int count = 0;
 281             while (reader.hasNext() && count < message.max) {
 282                 final Indexed<DataJournalEntry> next = reader.next();
 283                 if (next.index() > message.toSequenceNr) {
 284                     break;
 285                 }
 286
 287                 LOG.trace("{}: replay {}", persistenceId, next);
 288                 updateLargestSize(next.size());
 289                 final DataJournalEntry entry = next.entry();
 290                 verify(entry instanceof FromPersistence, "Unexpected entry %s", entry);
 291
 292                 final PersistentRepr repr = ((FromPersistence) entry).toRepr(persistenceId, next.index());
 293                 LOG.debug("{}: replaying {}", persistenceId, repr);
 294                 message.replayCallback.accept(repr);
 295                 count++;
 296             }
 297             LOG.debug("{}: successfully replayed {} entries", persistenceId, count);
 298         } catch (Exception e) {
 299             LOG.warn("{}: failed to replay messages for {}", persistenceId, message, e);
 300             message.promise.failure(e);
 301         } finally {
 302             message.promise.success(null);
 303         }
 304     }
 305
 306     @SuppressWarnings("checkstyle:illegalCatch")
 307     private void handleWriteMessages(final WriteMessages message) {
 308         ensureOpen();
 309
 310         final SegmentedJournalWriter<DataJournalEntry> writer = dataJournal.writer();
 311         final long startTicks = System.nanoTime();
 312         final int count = message.requests.size();
 313         final long start = writer.getLastIndex();
 314
 315         for (int i = 0; i < count; ++i) {
 316             final long mark = writer.getLastIndex();
 317             try {
 318                 writeRequest(writer, message.requests.get(i));
 319             } catch (Exception e) {
 320                 LOG.warn("{}: failed to write out request", persistenceId, e);
 321                 message.results.get(i).success(Optional.of(e));
 322                 writer.truncate(mark);
 323                 continue;
 324             }
 325
 326             message.results.get(i).success(Optional.empty());
 327         }
 328         writer.flush();
 329         batchWriteTime.update(System.nanoTime() - startTicks, TimeUnit.NANOSECONDS);
 330         messageWriteCount.mark(writer.getLastIndex() - start);
 331     }
 332
 333     private void writeRequest(final SegmentedJournalWriter<DataJournalEntry> writer, final AtomicWrite request) {
 334         for (PersistentRepr repr : CollectionConverters.asJava(request.payload())) {
 335             final Object payload = repr.payload();
 336             if (!(payload instanceof Serializable)) {
 337                 throw new UnsupportedOperationException("Non-serializable payload encountered " + payload.getClass());
 338             }
 339
 340             final int size = writer.append(new ToPersistence(repr)).size();
 341             messageSize.update(size);
 342             updateLargestSize(size);
 343         }
 344     }
 345
 346     private void handleUnknown(final Object message) {
 347         LOG.error("{}: Received unknown message {}", persistenceId, message);
 348     }
 349
 350     private void updateLargestSize(final int size) {
 351         if (size > largestObservedSize) {
 352             largestObservedSize = size;
 353         }
 354     }
 355
 356     private void ensureOpen() {
 357         if (dataJournal != null) {
 358             verifyNotNull(deleteJournal);
 359             return;
 360         }
 361
 362         deleteJournal = SegmentedJournal.<Long>builder().withDirectory(directory).withName("delete")
 363                 .withNamespace(DELETE_NAMESPACE).withMaxSegmentSize(DELETE_SEGMENT_SIZE).build();
 364         final Indexed<Long> lastEntry = deleteJournal.writer().getLastEntry();
 365         lastDelete = lastEntry == null ? 0 : lastEntry.entry();
 366
 367         dataJournal = SegmentedJournal.<DataJournalEntry>builder()
 368                 .withStorageLevel(storage).withDirectory(directory).withName("data")
 369                 .withNamespace(Namespace.builder()
 370                     .register(new DataJournalEntrySerializer(context().system()),
 371                         FromPersistence.class, ToPersistence.class)
 372                     .build())
 373                 .withMaxEntrySize(maxEntrySize).withMaxSegmentSize(maxSegmentSize)
 374                 .build();
 375         final SegmentedJournalWriter<DataJournalEntry> writer = dataJournal.writer();
 376         writer.commit(lastDelete);
 377         LOG.debug("{}: journal open with last index {}, deleted to {}", persistenceId, writer.getLastIndex(),
 378             lastDelete);
 379     }
 380 }