Noop peer recoveries on closed index

Author: ywelsch

server/src/main/java/org/elasticsearch/index/engine/InternalEngine.java

@@ -2558,6 +2558,10 @@ public Translog.Snapshot newChangesSnapshot(String source, MapperService mapperS
     @Override
     public boolean hasCompleteOperationHistory(String source, MapperService mapperService, long startingSeqNo) throws IOException {
         final long currentLocalCheckpoint = getLocalCheckpointTracker().getCheckpoint();
+        // avoid scanning translog if not necessary
+        if (startingSeqNo > currentLocalCheckpoint) {
+            return true;
+        }
         final LocalCheckpointTracker tracker = new LocalCheckpointTracker(startingSeqNo, startingSeqNo - 1);
         try (Translog.Snapshot snapshot = getTranslog().newSnapshotFromMinSeqNo(startingSeqNo)) {
             Translog.Operation operation;

server/src/main/java/org/elasticsearch/index/engine/ReadOnlyEngine.java

@@ -300,7 +300,7 @@ public int estimateNumberOfHistoryOperations(String source, MapperService mapper
 
     @Override
     public boolean hasCompleteOperationHistory(String source, MapperService mapperService, long startingSeqNo) throws IOException {
-        return false;
+        return startingSeqNo > seqNoStats.getLocalCheckpoint();
     }
 
     @Override

server/src/test/java/org/elasticsearch/indices/state/CloseIndexIT.java

@@ -34,6 +34,7 @@
 import org.elasticsearch.index.IndexNotFoundException;
 import org.elasticsearch.index.IndexSettings;
 import org.elasticsearch.indices.IndexClosedException;
+import org.elasticsearch.indices.recovery.RecoveryState;
 import org.elasticsearch.test.BackgroundIndexer;
 import org.elasticsearch.test.ESIntegTestCase;
 
@@ -50,6 +51,7 @@
 import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAcked;
 import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertHitCount;
 import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.empty;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.is;
@@ -338,6 +340,33 @@ public void testCloseIndexWaitForActiveShards() throws Exception {
         assertIndexIsClosed(indexName);
     }
 
+    public void testNoopPeerRecoveriesWhenIndexClosed() throws Exception {
+        final String indexName = "peer-recovery-test";
+        int numberOfReplicas = between(1, 2);
+        internalCluster().ensureAtLeastNumDataNodes(numberOfReplicas + between(1, 2));
+        createIndex(indexName, Settings.builder()
+            .put(IndexMetaData.SETTING_NUMBER_OF_SHARDS, 1)
+            .put(IndexMetaData.SETTING_NUMBER_OF_REPLICAS, numberOfReplicas)
+            .put("index.routing.rebalance.enable", "none")
+            .build());
+        indexRandom(randomBoolean(), false, randomBoolean(), IntStream.range(0, randomIntBetween(0, 50))
+            .mapToObj(i -> client().prepareIndex(indexName, "_doc").setSource("num", i)).collect(toList()));
+        ensureGreen(indexName);
+
+        // Closing an index should execute noop peer recovery
+        assertAcked(client().admin().indices().prepareClose(indexName).get());
+        assertIndexIsClosed(indexName);
+        ensureGreen(indexName);
+        assertNoFileBasedRecovery(indexName);
+
+        // Open a closed index should execute noop recovery
+        assertAcked(client().admin().indices().prepareOpen(indexName).get());
+        assertIndexIsOpened(indexName);
+        ensureGreen(indexName);
+        assertNoFileBasedRecovery(indexName);
+        internalCluster().assertSameDocIdsOnShards();
+    }
+
     static void assertIndexIsClosed(final String... indices) {
         final ClusterState clusterState = client().admin().cluster().prepareState().get().getState();
         for (String index : indices) {
@@ -383,4 +412,12 @@ static void assertException(final Throwable throwable, final String indexName) {
             fail("Unexpected exception: " + t);
         }
     }
+
+    void assertNoFileBasedRecovery(String indexName) {
+        for (RecoveryState recovery : client().admin().indices().prepareRecoveries(indexName).get().shardRecoveryStates().get(indexName)) {
+            if (recovery.getPrimary() == false) {
+                assertThat(recovery.getIndex().fileDetails(), empty());
+            }
+        }
+    }
 }