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

   1 /*
   2  * Copyright (c) 2014 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
   9 package org.opendaylight.controller.cluster.raft;
  10
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.base.Stopwatch;
  13 import java.util.concurrent.TimeUnit;
  14
  15 public class FollowerLogInformationImpl implements FollowerLogInformation {
  16     private final Stopwatch stopwatch = Stopwatch.createUnstarted();
  17
  18     private final RaftActorContext context;
  19
  20     private long nextIndex;
  21
  22     private long matchIndex;
  23
  24     private long lastReplicatedIndex = -1L;
  25
  26     private final Stopwatch lastReplicatedStopwatch = Stopwatch.createUnstarted();
  27
  28     private short payloadVersion = -1;
  29
  30     // Assume the HELIUM_VERSION version initially for backwards compatibility until we obtain the follower's
  31     // actual version via AppendEntriesReply. Although we no longer support the Helium version, a pre-Boron
  32     // follower will not have the version field in AppendEntriesReply so it will be set to 0 which is
  33     // HELIUM_VERSION.
  34     private short raftVersion = RaftVersions.HELIUM_VERSION;
  35
  36     private final PeerInfo peerInfo;
  37
  38     public FollowerLogInformationImpl(PeerInfo peerInfo, long matchIndex, RaftActorContext context) {
  39         this.nextIndex = context.getCommitIndex();
  40         this.matchIndex = matchIndex;
  41         this.context = context;
  42         this.peerInfo = Preconditions.checkNotNull(peerInfo);
  43     }
  44
  45     @Override
  46     public long incrNextIndex() {
  47         return nextIndex++;
  48     }
  49
  50     @Override
  51     public long decrNextIndex() {
  52         return nextIndex--;
  53     }
  54
  55     @Override
  56     public boolean setNextIndex(long nextIndex) {
  57         if(this.nextIndex != nextIndex) {
  58             this.nextIndex = nextIndex;
  59             return true;
  60         }
  61
  62         return false;
  63     }
  64
  65     @Override
  66     public long incrMatchIndex(){
  67         return matchIndex++;
  68     }
  69
  70     @Override
  71     public boolean setMatchIndex(long matchIndex) {
  72         if(this.matchIndex != matchIndex) {
  73             this.matchIndex = matchIndex;
  74             return true;
  75         }
  76
  77         return false;
  78     }
  79
  80     @Override
  81     public String getId() {
  82         return peerInfo.getId();
  83     }
  84
  85     @Override
  86     public long getNextIndex() {
  87         return nextIndex;
  88     }
  89
  90     @Override
  91     public long getMatchIndex() {
  92         return matchIndex;
  93     }
  94
  95     @Override
  96     public boolean isFollowerActive() {
  97         if(peerInfo.getVotingState() == VotingState.VOTING_NOT_INITIALIZED) {
  98             return false;
  99         }
 100
 101         long elapsed = stopwatch.elapsed(TimeUnit.MILLISECONDS);
 102         return (stopwatch.isRunning()) &&
 103                 (elapsed <= context.getConfigParams().getElectionTimeOutInterval().toMillis());
 104     }
 105
 106     @Override
 107     public void markFollowerActive() {
 108         if (stopwatch.isRunning()) {
 109             stopwatch.reset();
 110         }
 111         stopwatch.start();
 112     }
 113
 114     @Override
 115     public void markFollowerInActive() {
 116         if (stopwatch.isRunning()) {
 117             stopwatch.stop();
 118         }
 119     }
 120
 121     @Override
 122     public long timeSinceLastActivity() {
 123         return stopwatch.elapsed(TimeUnit.MILLISECONDS);
 124     }
 125
 126     @Override
 127     public boolean okToReplicate() {
 128         if(peerInfo.getVotingState() == VotingState.VOTING_NOT_INITIALIZED) {
 129             return false;
 130         }
 131
 132         // Return false if we are trying to send duplicate data before the heartbeat interval
 133         if(getNextIndex() == lastReplicatedIndex){
 134             if(lastReplicatedStopwatch.elapsed(TimeUnit.MILLISECONDS) < context.getConfigParams()
 135                     .getHeartBeatInterval().toMillis()){
 136                 return false;
 137             }
 138         }
 139
 140         resetLastReplicated();
 141         return true;
 142     }
 143
 144     private void resetLastReplicated(){
 145         lastReplicatedIndex = getNextIndex();
 146         if(lastReplicatedStopwatch.isRunning()){
 147             lastReplicatedStopwatch.reset();
 148         }
 149         lastReplicatedStopwatch.start();
 150     }
 151
 152     @Override
 153     public short getPayloadVersion() {
 154         return payloadVersion;
 155     }
 156
 157     @Override
 158     public void setPayloadVersion(short payloadVersion) {
 159         this.payloadVersion = payloadVersion;
 160     }
 161
 162     @Override
 163     public short getRaftVersion() {
 164         return raftVersion;
 165     }
 166
 167     @Override
 168     public void setRaftVersion(short raftVersion) {
 169         this.raftVersion = raftVersion;
 170     }
 171
 172     @Override
 173     public String toString() {
 174         return "FollowerLogInformationImpl [id=" + getId() + ", nextIndex=" + nextIndex + ", matchIndex=" + matchIndex
 175                 + ", lastReplicatedIndex=" + lastReplicatedIndex + ", votingState=" + peerInfo.getVotingState()
 176                 + ", stopwatch=" + stopwatch.elapsed(TimeUnit.MILLISECONDS) + ", followerTimeoutMillis="
 177                 + context.getConfigParams().getElectionTimeOutInterval().toMillis() + "]";
 178     }
 179 }