Set default interval for search replicas on the setting as 5s.

Signed-off-by: Marc Handalian <[email protected]>

server/src/internalClusterTest/java/org/opensearch/indices/settings/SearchOnlyReplicaIT.java

@@ -8,6 +8,8 @@
 
 package org.opensearch.indices.settings;
 
+import org.opensearch.action.admin.indices.settings.get.GetSettingsRequest;
+import org.opensearch.action.admin.indices.settings.get.GetSettingsResponse;
 import org.opensearch.action.support.WriteRequest;
 import org.opensearch.cluster.ClusterState;
 import org.opensearch.cluster.metadata.IndexMetadata;
@@ -21,18 +23,20 @@
 import org.opensearch.test.OpenSearchIntegTestCase;
 
 import java.io.IOException;
+import java.util.concurrent.ExecutionException;
 
 import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_NUMBER_OF_SEARCH_REPLICAS;
 import static org.opensearch.cluster.metadata.IndexMetadata.SETTING_REPLICATION_TYPE;
 import static org.opensearch.cluster.routing.UnassignedInfo.INDEX_DELAYED_NODE_LEFT_TIMEOUT_SETTING;
+import static org.opensearch.index.IndexSettings.INDEX_REPLICATION_INTERVAL_SETTING;
 import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertHitCount;
 
 @OpenSearchIntegTestCase.ClusterScope(scope = OpenSearchIntegTestCase.Scope.TEST, numDataNodes = 0)
 public class SearchOnlyReplicaIT extends OpenSearchIntegTestCase {
 
     private static final String TEST_INDEX = "test_index";
 
-    @Override
+    @Override /**/
     protected Settings featureFlagSettings() {
         return Settings.builder().put(super.featureFlagSettings()).put(FeatureFlags.READER_WRITER_SPLIT_EXPERIMENTAL, Boolean.TRUE).build();
     }
@@ -175,6 +179,46 @@ public void testSearchReplicaScaling() {
         assertActiveSearchShards(0);
     }
 
+    public void testDefaultReplicationSettings() throws ExecutionException, InterruptedException {
+        internalCluster().startNodes(2);
+        createIndex(
+            TEST_INDEX,
+            Settings.builder()
+                .put(indexSettings())
+                .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, 0)
+                .put(IndexMetadata.SETTING_NUMBER_OF_SEARCH_REPLICAS, 0)
+                .build()
+        );
+        ensureGreen(TEST_INDEX);
+        // assert settings
+        Metadata metadata = client().admin().cluster().prepareState().get().getState().metadata();
+        IndexMetadata indexMetadata = metadata.index(TEST_INDEX);
+        Settings settings = indexMetadata.getSettings();
+        int numSearchReplicas = Integer.parseInt(settings.get(SETTING_NUMBER_OF_SEARCH_REPLICAS));
+        assertEquals(0, numSearchReplicas);
+
+        GetSettingsResponse settingsResponse = client().admin()
+            .indices()
+            .getSettings(new GetSettingsRequest().indices(TEST_INDEX).includeDefaults(true))
+            .get();
+        assertEquals("0ms", settingsResponse.getSetting(TEST_INDEX, INDEX_REPLICATION_INTERVAL_SETTING.getKey()));
+
+        // assert cluster state & routing table
+        assertActiveSearchShards(0);
+
+        // Add a search replica
+        client().admin()
+            .indices()
+            .prepareUpdateSettings(TEST_INDEX)
+            .setSettings(Settings.builder().put(SETTING_NUMBER_OF_SEARCH_REPLICAS, 1))
+            .get();
+        ensureGreen(TEST_INDEX);
+        assertActiveSearchShards(1);
+
+        settingsResponse = client().admin().indices().getSettings(new GetSettingsRequest().indices(TEST_INDEX).includeDefaults(true)).get();
+        assertEquals("5s", settingsResponse.getSetting(TEST_INDEX, INDEX_REPLICATION_INTERVAL_SETTING.getKey()));
+    }
+
     /**
      * Helper to assert counts of active shards for each type.
      */

server/src/main/java/org/opensearch/cluster/metadata/MetadataCreateIndexService.java

@@ -156,7 +156,6 @@
 import static org.opensearch.cluster.metadata.Metadata.DEFAULT_REPLICA_COUNT_SETTING;
 import static org.opensearch.cluster.metadata.MetadataIndexTemplateService.findContextTemplateName;
 import static org.opensearch.index.IndexModule.INDEX_STORE_TYPE_SETTING;
-import static org.opensearch.index.IndexSettings.INDEX_REPLICATION_INTERVAL_SETTING;
 import static org.opensearch.index.IndexSettings.INDEX_TRANSLOG_FLUSH_THRESHOLD_SIZE_SETTING;
 import static org.opensearch.indices.IndicesService.CLUSTER_REPLICATION_TYPE_SETTING;
 import static org.opensearch.node.remotestore.RemoteStoreNodeAttribute.isRemoteDataAttributePresent;
@@ -1096,10 +1095,6 @@ private static void updateSearchOnlyReplicas(Settings requestSettings, Settings.
                 );
             }
             builder.put(SETTING_NUMBER_OF_SEARCH_REPLICAS, INDEX_NUMBER_OF_SEARCH_REPLICAS_SETTING.get(requestSettings));
-            if (INDEX_REPLICATION_INTERVAL_SETTING.exists(requestSettings) == false) {
-                // set the search replica to a default interval
-                builder.put(INDEX_REPLICATION_INTERVAL_SETTING.getKey(), TimeValue.timeValueSeconds(5));
-            }
         }
     }
 

server/src/main/java/org/opensearch/index/IndexService.java

@@ -1096,8 +1096,8 @@ private void updateReplicationInterval() {
     }
 
     /**
-     * Gets the replication interval seen by the index service. Index setting overrides takes the highest precedence.
-     * @return the refresh interval.
+     * Gets the replication interval seen by the index service.
+     * @return the replication interval.
      */
     private TimeValue getReplicationInterval() {
         return getIndexSettings().getReplicationInterval();

server/src/main/java/org/opensearch/index/IndexSettings.java

@@ -70,6 +70,7 @@
 import java.util.function.UnaryOperator;
 
 import static org.opensearch.Version.V_2_7_0;
+import static org.opensearch.cluster.metadata.IndexMetadata.INDEX_NUMBER_OF_SEARCH_REPLICAS_SETTING;
 import static org.opensearch.common.util.FeatureFlags.SEARCHABLE_SNAPSHOT_EXTENDED_COMPATIBILITY;
 import static org.opensearch.index.codec.fuzzy.FuzzySetParameters.DEFAULT_FALSE_POSITIVE_PROBABILITY;
 import static org.opensearch.index.mapper.MapperService.INDEX_MAPPING_DEPTH_LIMIT_SETTING;
@@ -376,14 +377,14 @@ public static IndexMergePolicy fromString(String text) {
      * pull based replication is disabled.
      */
     public static final TimeValue DEFAULT_REPLICATION_INTERVAL = TimeValue.ZERO;
+    public static final TimeValue DEFAULT_SEARCH_REPLICA_INTERVAL = TimeValue.timeValueSeconds(5);
     public static final TimeValue MINIMUM_REPLICATION_INTERVAL = TimeValue.ZERO;
-    public static final Setting<TimeValue> INDEX_REPLICATION_INTERVAL_SETTING = Setting.timeSetting(
-        "index.replication_interval",
-        DEFAULT_REPLICATION_INTERVAL,
-        MINIMUM_REPLICATION_INTERVAL,
-        Property.Dynamic,
-        Property.IndexScope
-    );
+    public static final Setting<TimeValue> INDEX_REPLICATION_INTERVAL_SETTING = Setting.timeSetting("index.replication_interval", (s) -> {
+        if (INDEX_NUMBER_OF_SEARCH_REPLICAS_SETTING.get(s) > 0) {
+            return DEFAULT_SEARCH_REPLICA_INTERVAL;
+        }
+        return DEFAULT_REPLICATION_INTERVAL;
+    }, MINIMUM_REPLICATION_INTERVAL, Property.Dynamic, Property.IndexScope);
 
     public static final Setting<ByteSizeValue> INDEX_TRANSLOG_FLUSH_THRESHOLD_SIZE_SETTING = Setting.byteSizeSetting(
         "index.translog.flush_threshold_size",
@@ -1198,10 +1199,10 @@ public IndexSettings(final IndexMetadata indexMetadata, final Settings nodeSetti
         if (FeatureFlags.READER_WRITER_SPLIT_EXPERIMENTAL_SETTING.get(nodeSettings)) {
             // Move setting registration to IndexScopedSettings when feature flag is removed.
             scopedSettings.registerSetting(INDEX_REPLICATION_INTERVAL_SETTING);
-            replicationInterval = scopedSettings.get(INDEX_REPLICATION_INTERVAL_SETTING);
+            setReplicationInterval(scopedSettings.get(INDEX_REPLICATION_INTERVAL_SETTING));
             scopedSettings.addSettingsUpdateConsumer(INDEX_REPLICATION_INTERVAL_SETTING, this::setReplicationInterval);
         } else {
-            replicationInterval = TimeValue.ZERO;
+            replicationInterval = DEFAULT_REPLICATION_INTERVAL;
         }
     }
 

server/src/main/java/org/opensearch/indices/replication/SegmentReplicator.java

@@ -62,13 +62,7 @@ public void onReplicationDone(SegmentReplicationState state) {
 
                 @Override
                 public void onReplicationFailure(SegmentReplicationState state, ReplicationFailedException e, boolean sendShardFailure) {
-                    logger.error(
-                        () -> new ParameterizedMessage(
-                            "Failed segment replication for {}",
-                            shard.shardId()
-                        ),
-                        e
-                    );
+                    logger.error(() -> new ParameterizedMessage("Failed segment replication for {}", shard.shardId()), e);
                     if (sendShardFailure) {
                         shard.failShard("unrecoverable replication failure", e);
                     }