X-Git-Url: https://git.opendaylight.org/gerrit/gitweb?a=blobdiff_plain;f=opendaylight%2Fmd-sal%2Fsal-akka-raft%2Fsrc%2Fmain%2Fjava%2Forg%2Fopendaylight%2Fcontroller%2Fcluster%2Fraft%2Fbehaviors%2FSyncStatusTracker.java;h=2b700ffc43c1ec80cce36f2ab4293cfaebc09547;hb=9b319f491af1c65705b69e8a182aab5006a2f959;hp=0986565bac2748b94037a7a19f3f4c6a2912d651;hpb=660c3e22ca97bc613ea6f6288503620bba6fb233;p=controller.git

diff --git a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/SyncStatusTracker.java b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/SyncStatusTracker.java
index 0986565bac..2b700ffc43 100644
--- a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/SyncStatusTracker.java
+++ b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/behaviors/SyncStatusTracker.java
@@ -5,12 +5,15 @@
  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
  * and is available at http://www.eclipse.org/legal/epl-v10.html
  */
-
 package org.opendaylight.controller.cluster.raft.behaviors;
 
+import static com.google.common.base.Preconditions.checkArgument;
+import static java.util.Objects.requireNonNull;
+
 import akka.actor.ActorRef;
-import com.google.common.base.Preconditions;
 import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyncUpStatus;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * The SyncStatusTracker tracks if a Follower is in sync with any given Leader or not
@@ -21,51 +24,63 @@ import org.opendaylight.controller.cluster.raft.base.messages.FollowerInitialSyn
  * sync if it is behind by 'syncThreshold' commits.
  */
 public class SyncStatusTracker {
+    private static final class LeaderInfo {
+        final long minimumCommitIndex;
+        final String leaderId;
+
+        LeaderInfo(final String leaderId, final long minimumCommitIndex) {
+            this.leaderId = requireNonNull(leaderId);
+            this.minimumCommitIndex = minimumCommitIndex;
+        }
+    }
+
+    private static final Logger LOG = LoggerFactory.getLogger(SyncStatusTracker.class);
 
     private static final boolean IN_SYNC = true;
     private static final boolean NOT_IN_SYNC = false;
-    private static final boolean FORCE_STATUS_CHANGE = true;
 
-    private final String id;
-    private String syncedLeaderId = null;
+    private final long syncThreshold;
     private final ActorRef actor;
-    private final int syncThreshold;
-    private boolean syncStatus = false;
-    private long minimumExpectedIndex = -2L;
+    private final String id;
+
+    private LeaderInfo syncTarget;
+    private boolean syncStatus;
 
-    public SyncStatusTracker(ActorRef actor, String id, int syncThreshold) {
-        this.actor = Preconditions.checkNotNull(actor, "actor should not be null");
-        this.id = Preconditions.checkNotNull(id, "id should not be null");
-        Preconditions.checkArgument(syncThreshold >= 0, "syncThreshold should be greater than or equal to 0");
+    public SyncStatusTracker(final ActorRef actor, final String id, final long syncThreshold) {
+        this.actor = requireNonNull(actor, "actor should not be null");
+        this.id = requireNonNull(id, "id should not be null");
+        checkArgument(syncThreshold >= 0, "syncThreshold should be greater than or equal to 0");
         this.syncThreshold = syncThreshold;
     }
 
-    public void update(String leaderId, long leaderCommit, long commitIndex) {
-        Preconditions.checkNotNull(leaderId, "leaderId should not be null");
+    public void update(final String leaderId, final long leaderCommit, final long commitIndex) {
+        requireNonNull(leaderId, "leaderId should not be null");
 
-        if (!leaderId.equals(syncedLeaderId)) {
-            minimumExpectedIndex = leaderCommit;
-            changeSyncStatus(NOT_IN_SYNC, FORCE_STATUS_CHANGE);
-            syncedLeaderId = leaderId;
+        if (syncTarget == null || !leaderId.equals(syncTarget.leaderId)) {
+            LOG.debug("{}: Last sync leader does not match current leader {}, need to catch up to {}", id,
+                leaderId, leaderCommit);
+            changeSyncStatus(NOT_IN_SYNC, true);
+            syncTarget = new LeaderInfo(leaderId, leaderCommit);
             return;
         }
 
-        if (leaderCommit - commitIndex > syncThreshold) {
-            changeSyncStatus(NOT_IN_SYNC);
-        } else if (leaderCommit - commitIndex <= syncThreshold && commitIndex >= minimumExpectedIndex) {
-            changeSyncStatus(IN_SYNC);
+        final long lag = leaderCommit - commitIndex;
+        if (lag > syncThreshold) {
+            LOG.debug("{}: Lagging {} entries behind leader {}", id, lag, leaderId);
+            changeSyncStatus(NOT_IN_SYNC, false);
+        } else if (commitIndex >= syncTarget.minimumCommitIndex) {
+            LOG.debug("{}: Lagging {} entries behind leader {} and reached {} (of expected {})", id, lag, leaderId,
+                commitIndex, syncTarget.minimumCommitIndex);
+            changeSyncStatus(IN_SYNC, false);
         }
     }
 
-    private void changeSyncStatus(boolean newSyncStatus) {
-        changeSyncStatus(newSyncStatus, !FORCE_STATUS_CHANGE);
-    }
-
-    private void changeSyncStatus(boolean newSyncStatus, boolean forceStatusChange) {
-        if (syncStatus == newSyncStatus && !forceStatusChange) {
-            return;
+    private void changeSyncStatus(final boolean newSyncStatus, final boolean forceStatusChange) {
+        if (forceStatusChange || newSyncStatus != syncStatus) {
+            actor.tell(new FollowerInitialSyncUpStatus(newSyncStatus, id), ActorRef.noSender());
+            syncStatus = newSyncStatus;
+        } else {
+            LOG.trace("{}: No change in sync status of, dampening message", id);
         }
-        actor.tell(new FollowerInitialSyncUpStatus(newSyncStatus, id), ActorRef.noSender());
-        syncStatus = newSyncStatus;
     }
 }