opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/ReplicatedLogImpl.java

   1 /*
   2  * Copyright (c) 2015 Cisco Systems, Inc. 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.cluster.raft;
   9
  10 import akka.japi.Procedure;
  11 import com.google.common.base.Preconditions;
  12 import java.util.Collections;
  13 import java.util.List;
  14 import org.opendaylight.controller.cluster.raft.base.messages.DeleteEntries;
  15 import org.opendaylight.controller.cluster.raft.behaviors.RaftActorBehavior;
  16
  17 /**
  18  * Implementation of ReplicatedLog used by the RaftActor.
  19  */
  20 class ReplicatedLogImpl extends AbstractReplicatedLogImpl {
  21     private static final int DATA_SIZE_DIVIDER = 5;
  22
  23     private long dataSizeSinceLastSnapshot = 0L;
  24     private final RaftActorContext context;
  25     private final RaftActorBehavior currentBehavior;
  26
  27     private final Procedure<DeleteEntries> deleteProcedure = new Procedure<DeleteEntries>() {
  28         @Override
  29         public void apply(final DeleteEntries notUsed) {
  30         }
  31     };
  32
  33     static ReplicatedLog newInstance(final Snapshot snapshot, final RaftActorContext context,
  34             final RaftActorBehavior currentBehavior) {
  35         return new ReplicatedLogImpl(snapshot.getLastAppliedIndex(), snapshot.getLastAppliedTerm(),
  36                 snapshot.getUnAppliedEntries(), context, currentBehavior);
  37     }
  38
  39     static ReplicatedLog newInstance(final RaftActorContext context, final RaftActorBehavior currentBehavior) {
  40         return new ReplicatedLogImpl(-1L, -1L, Collections.<ReplicatedLogEntry>emptyList(), context,
  41                 currentBehavior);
  42     }
  43
  44     private ReplicatedLogImpl(final long snapshotIndex, final long snapshotTerm, final List<ReplicatedLogEntry> unAppliedEntries,
  45             final RaftActorContext context, final RaftActorBehavior currentBehavior) {
  46         super(snapshotIndex, snapshotTerm, unAppliedEntries);
  47         this.context = Preconditions.checkNotNull(context);
  48         this.currentBehavior = Preconditions.checkNotNull(currentBehavior);
  49     }
  50
  51     @Override
  52     public void removeFromAndPersist(final long logEntryIndex) {
  53         // FIXME: Maybe this should be done after the command is saved
  54         long adjustedIndex = removeFrom(logEntryIndex);
  55         if(adjustedIndex >= 0) {
  56             context.getPersistenceProvider().persist(new DeleteEntries(adjustedIndex), deleteProcedure);
  57         }
  58     }
  59
  60     @Override
  61     public void appendAndPersist(final ReplicatedLogEntry replicatedLogEntry) {
  62         appendAndPersist(replicatedLogEntry, null);
  63     }
  64
  65     @Override
  66     public void captureSnapshotIfReady(final ReplicatedLogEntry replicatedLogEntry) {
  67         long journalSize = replicatedLogEntry.getIndex() + 1;
  68         long dataThreshold = context.getTotalMemory() *
  69                 context.getConfigParams().getSnapshotDataThresholdPercentage() / 100;
  70
  71         if ((journalSize % context.getConfigParams().getSnapshotBatchCount() == 0
  72                 || getDataSizeForSnapshotCheck() > dataThreshold)) {
  73
  74             boolean started = context.getSnapshotManager().capture(replicatedLogEntry,
  75                     currentBehavior.getReplicatedToAllIndex());
  76             if (started) {
  77                 if (!context.hasFollowers()) {
  78                     dataSizeSinceLastSnapshot = 0;
  79                 }
  80             }
  81         }
  82     }
  83
  84     private long getDataSizeForSnapshotCheck() {
  85         long dataSizeForCheck = dataSize();
  86         if (!context.hasFollowers()) {
  87             // When we do not have followers we do not maintain an in-memory log
  88             // due to this the journalSize will never become anything close to the
  89             // snapshot batch count. In fact will mostly be 1.
  90             // Similarly since the journal's dataSize depends on the entries in the
  91             // journal the journal's dataSize will never reach a value close to the
  92             // memory threshold.
  93             // By maintaining the dataSize outside the journal we are tracking essentially
  94             // what we have written to the disk however since we no longer are in
  95             // need of doing a snapshot just for the sake of freeing up memory we adjust
  96             // the real size of data by the DATA_SIZE_DIVIDER so that we do not snapshot as often
  97             // as if we were maintaining a real snapshot
  98             dataSizeForCheck = dataSizeSinceLastSnapshot / DATA_SIZE_DIVIDER;
  99         }
 100         return dataSizeForCheck;
 101     }
 102
 103     @Override
 104     public void appendAndPersist(final ReplicatedLogEntry replicatedLogEntry,
 105             final Procedure<ReplicatedLogEntry> callback)  {
 106
 107         if (context.getLogger().isDebugEnabled()) {
 108             context.getLogger().debug("{}: Append log entry and persist {} ", context.getId(), replicatedLogEntry);
 109         }
 110
 111         // FIXME : By adding the replicated log entry to the in-memory journal we are not truly ensuring durability of the logs
 112         append(replicatedLogEntry);
 113
 114         // When persisting events with persist it is guaranteed that the
 115         // persistent actor will not receive further commands between the
 116         // persist call and the execution(s) of the associated event
 117         // handler. This also holds for multiple persist calls in context
 118         // of a single command.
 119         context.getPersistenceProvider().persist(replicatedLogEntry,
 120             new Procedure<ReplicatedLogEntry>() {
 121                 @Override
 122                 public void apply(final ReplicatedLogEntry param) throws Exception {
 123                     context.getLogger().debug("{}: persist complete {}", context.getId(), param);
 124
 125                     int logEntrySize = param.size();
 126                     dataSizeSinceLastSnapshot += logEntrySize;
 127
 128                     if (callback != null) {
 129                         callback.apply(param);
 130                     }
 131                 }
 132             }
 133         );
 134     }
 135 }