Force install snapshot when follower log is ahead

[controller.git] / opendaylight / md-sal / sal-akka-raft / src / main / java / org / opendaylight / controller / cluster / raft / AbstractReplicatedLogImpl.java

diff --git a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/AbstractReplicatedLogImpl.java b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/AbstractReplicatedLogImpl.java
index e2aa16918e8ed0354f8543f8edd74b89474e4072..69b78458b61b62ffb6668653a4ae63019912f6a5 100644 (file)
--- a/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/AbstractReplicatedLogImpl.java
+++ b/opendaylight/md-sal/sal-akka-raft/src/main/java/org/opendaylight/controller/cluster/raft/AbstractReplicatedLogImpl.java
@@ -7,18 +7,25 @@
  */
 package org.opendaylight.controller.cluster.raft;
 
+import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Preconditions;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Abstract class handling the mapping of
  * logical LogEntry Index and the physical list index.
  */
 public abstract class AbstractReplicatedLogImpl implements ReplicatedLog {
+    private static final Logger LOG = LoggerFactory.getLogger(AbstractReplicatedLogImpl.class);
+
+    private final String logContext;
 
     // We define this as ArrayList so we can use ensureCapacity.
-    protected ArrayList<ReplicatedLogEntry> journal;
+    private ArrayList<ReplicatedLogEntry> journal;
 
     private long snapshotIndex = -1;
     private long snapshotTerm = -1;
@@ -27,17 +34,22 @@ public abstract class AbstractReplicatedLogImpl implements ReplicatedLog {
     private ArrayList<ReplicatedLogEntry> snapshottedJournal;
     private long previousSnapshotIndex = -1;
     private long previousSnapshotTerm = -1;
-    protected int dataSize = 0;
+    private int dataSize = 0;
 
     public AbstractReplicatedLogImpl(long snapshotIndex,
-        long snapshotTerm, List<ReplicatedLogEntry> unAppliedEntries) {
+        long snapshotTerm, List<ReplicatedLogEntry> unAppliedEntries, String logContext) {
         this.snapshotIndex = snapshotIndex;
         this.snapshotTerm = snapshotTerm;
-        this.journal = new ArrayList<>(unAppliedEntries);
+        this.logContext = logContext;
+
+        this.journal = new ArrayList<>(unAppliedEntries.size());
+        for(ReplicatedLogEntry entry: unAppliedEntries) {
+            append(entry);
+        }
     }
 
     public AbstractReplicatedLogImpl() {
-        this(-1L, -1L, Collections.<ReplicatedLogEntry>emptyList());
+        this(-1L, -1L, Collections.<ReplicatedLogEntry>emptyList(), "");
     }
 
     protected int adjustedIndex(long logEntryIndex) {
@@ -89,18 +101,33 @@ public abstract class AbstractReplicatedLogImpl implements ReplicatedLog {
     }
 
     @Override
-    public void removeFrom(long logEntryIndex) {
+    public long removeFrom(long logEntryIndex) {
         int adjustedIndex = adjustedIndex(logEntryIndex);
         if (adjustedIndex < 0 || adjustedIndex >= journal.size()) {
             // physical index should be less than list size and >= 0
-            return;
+            return -1;
+        }
+
+        for(int i = adjustedIndex; i < journal.size(); i++) {
+            dataSize -= journal.get(i).size();
         }
+
         journal.subList(adjustedIndex , journal.size()).clear();
+
+        return adjustedIndex;
     }
 
     @Override
-    public void append(ReplicatedLogEntry replicatedLogEntry) {
-        journal.add(replicatedLogEntry);
+    public boolean append(ReplicatedLogEntry replicatedLogEntry) {
+        if(replicatedLogEntry.getIndex() > lastIndex()) {
+            journal.add(replicatedLogEntry);
+            dataSize += replicatedLogEntry.size();
+            return true;
+        } else {
+            LOG.warn("{}: Cannot append new entry - new index {} is not greater than the last index {}",
+                    logContext, replicatedLogEntry.getIndex(), lastIndex(), new Exception("stack trace"));
+            return false;
+        }
     }
 
     @Override
@@ -110,20 +137,43 @@ public abstract class AbstractReplicatedLogImpl implements ReplicatedLog {
 
     @Override
     public List<ReplicatedLogEntry> getFrom(long logEntryIndex) {
-        return getFrom(logEntryIndex, journal.size());
+        return getFrom(logEntryIndex, journal.size(), NO_MAX_SIZE);
     }
 
     @Override
-    public List<ReplicatedLogEntry> getFrom(long logEntryIndex, int max) {
+    public List<ReplicatedLogEntry> getFrom(long logEntryIndex, int maxEntries, long maxDataSize) {
         int adjustedIndex = adjustedIndex(logEntryIndex);
         int size = journal.size();
         if (adjustedIndex >= 0 && adjustedIndex < size) {
             // physical index should be less than list size and >= 0
-            int maxIndex = adjustedIndex + max;
+            int maxIndex = adjustedIndex + maxEntries;
             if(maxIndex > size){
                 maxIndex = size;
             }
-            return new ArrayList<>(journal.subList(adjustedIndex, maxIndex));
+
+            if(maxDataSize == NO_MAX_SIZE) {
+                return new ArrayList<>(journal.subList(adjustedIndex, maxIndex));
+            } else {
+                List<ReplicatedLogEntry> retList = new ArrayList<>(maxIndex - adjustedIndex);
+                long totalSize = 0;
+                for(int i = adjustedIndex; i < maxIndex; i++) {
+                    ReplicatedLogEntry entry = journal.get(i);
+                    totalSize += entry.size();
+                    if(totalSize <= maxDataSize) {
+                        retList.add(entry);
+                    } else {
+                        if(retList.isEmpty()) {
+                            // Edge case - the first entry's size exceeds the threshold. We need to return
+                            // at least the first entry so add it here.
+                            retList.add(entry);
+                        }
+
+                        break;
+                    }
+                }
+
+                return retList;
+            }
         } else {
             return Collections.emptyList();
         }
@@ -164,12 +214,6 @@ public abstract class AbstractReplicatedLogImpl implements ReplicatedLog {
         return snapshotTerm;
     }
 
-    @Override
-    public abstract void appendAndPersist(ReplicatedLogEntry replicatedLogEntry);
-
-    @Override
-    public abstract void removeFromAndPersist(long index);
-
     @Override
     public void setSnapshotIndex(long snapshotIndex) {
         this.snapshotIndex = snapshotIndex;
@@ -187,10 +231,15 @@ public abstract class AbstractReplicatedLogImpl implements ReplicatedLog {
 
     @Override
     public void snapshotPreCommit(long snapshotCapturedIndex, long snapshotCapturedTerm) {
+        Preconditions.checkArgument(snapshotCapturedIndex >= snapshotIndex,
+                "snapshotCapturedIndex must be greater than or equal to snapshotIndex");
+
         snapshottedJournal = new ArrayList<>(journal.size());
 
-        snapshottedJournal.addAll(journal.subList(0, (int)(snapshotCapturedIndex - snapshotIndex)));
-        clear(0, (int) (snapshotCapturedIndex - snapshotIndex));
+        List<ReplicatedLogEntry> snapshotJournalEntries = journal.subList(0, (int) (snapshotCapturedIndex - snapshotIndex));
+
+        snapshottedJournal.addAll(snapshotJournalEntries);
+        snapshotJournalEntries.clear();
 
         previousSnapshotIndex = snapshotIndex;
         setSnapshotIndex(snapshotCapturedIndex);
@@ -224,4 +273,9 @@ public abstract class AbstractReplicatedLogImpl implements ReplicatedLog {
         snapshotTerm = previousSnapshotTerm;
         previousSnapshotTerm = -1;
     }
+
+    @VisibleForTesting
+    ReplicatedLogEntry getAtPhysicalIndex(int index) {
+        return journal.get(index);
+    }
 }