Make field_range optimization work with FrozenEngine (#69357)

Searchable snapshot indices that are mounted using the shared_cache option are now using the FrozenEngine. This engine does not properly implement getRawFieldRange, however, resulting in the index to be loaded on the cluster stat applier thread.
elastic · Feb 23, 2021 · e243e4d · e243e4d
1 parent f4fa74b
commit e243e4d
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Showing 4 changed files with 8 additions and 16 deletions.
diff --git a/server/src/main/java/org/elasticsearch/index/engine/ReadOnlyEngine.java b/server/src/main/java/org/elasticsearch/index/engine/ReadOnlyEngine.java
@@ -58,6 +58,8 @@
  */
 public class ReadOnlyEngine extends Engine {
 
+    public static final String FIELD_RANGE_SEARCH_SOURCE = "field_range";
+
     /**
      * Reader attributes used for read only engines. These attributes prevent loading term dictionaries on-heap even if the field is an
      * ID field.
@@ -578,7 +580,7 @@ public CompletionStats completionStats(String... fieldNamePatterns) {
      */
     @Override
     public ShardLongFieldRange getRawFieldRange(String field) throws IOException {
-        try (Searcher searcher = acquireSearcher("field_range")) {
+        try (Searcher searcher = acquireSearcher(FIELD_RANGE_SEARCH_SOURCE)) {
             final DirectoryReader directoryReader = searcher.getDirectoryReader();
 
             final byte[] minPackedValue = PointValues.getMinPackedValue(directoryReader, field);

diff --git a/x-pack/plugin/core/src/main/java/org/elasticsearch/index/engine/FrozenEngine.java b/x-pack/plugin/core/src/main/java/org/elasticsearch/index/engine/FrozenEngine.java
@@ -222,6 +222,7 @@ private Engine.Searcher openSearcher(String source, SearcherScope scope) throws
             case "segments":
             case "segments_stats":
             case "completion_stats":
+            case FIELD_RANGE_SEARCH_SOURCE: // special case for field_range - we use the cached point values reader
             case CAN_MATCH_SEARCH_SOURCE: // special case for can_match phase - we use the cached point values reader
                 maybeOpenReader = false;
                 break;
@@ -230,7 +231,7 @@ private Engine.Searcher openSearcher(String source, SearcherScope scope) throws
         }
         ElasticsearchDirectoryReader reader = maybeOpenReader ? getOrOpenReader() : getReader();
         if (reader == null) {
-            if (CAN_MATCH_SEARCH_SOURCE.equals(source)) {
+            if (CAN_MATCH_SEARCH_SOURCE.equals(source) || FIELD_RANGE_SEARCH_SOURCE.equals(source)) {
                 canMatchReader.incRef();
                 return new Searcher(source, canMatchReader, engineConfig.getSimilarity(), engineConfig.getQueryCache(),
                     engineConfig.getQueryCachingPolicy(), canMatchReader::decRef);

diff --git a/...indices/src/internalClusterTest/java/org/elasticsearch/index/engine/FrozenIndexTests.java b/...indices/src/internalClusterTest/java/org/elasticsearch/index/engine/FrozenIndexTests.java
@@ -9,7 +9,6 @@
 import org.elasticsearch.action.OriginalIndices;
 import org.elasticsearch.action.admin.cluster.state.ClusterStateResponse;
 import org.elasticsearch.action.admin.indices.stats.IndicesStatsResponse;
-import org.elasticsearch.action.admin.indices.stats.ShardStats;
 import org.elasticsearch.action.delete.DeleteResponse;
 import org.elasticsearch.action.index.IndexResponse;
 import org.elasticsearch.action.search.SearchRequest;
@@ -539,11 +538,6 @@ public void testComputesTimestampRangeFromMilliseconds() {
         assertTrue(timestampFieldRange.isComplete());
         assertThat(timestampFieldRange.getMin(), equalTo(Instant.parse("2010-01-05T01:02:03.456Z").toEpochMilli()));
         assertThat(timestampFieldRange.getMax(), equalTo(Instant.parse("2010-01-06T02:03:04.567Z").toEpochMilli()));
-
-        for (ShardStats shardStats : client().admin().indices().prepareStats("index").clear().setRefresh(true).get().getShards()) {
-            assertThat("shard " + shardStats.getShardRouting() + " refreshed to get the timestamp range",
-                    shardStats.getStats().refresh.getTotal(), greaterThanOrEqualTo(1L));
-        }
     }
 
     public void testComputesTimestampRangeFromNanoseconds() throws IOException {
@@ -575,11 +569,6 @@ public void testComputesTimestampRangeFromNanoseconds() throws IOException {
             equalTo(resolution.convert(Instant.parse("2010-01-05T01:02:03.456789012Z"))));
         assertThat(timestampFieldRange.getMax(),
             equalTo(resolution.convert(Instant.parse("2010-01-06T02:03:04.567890123Z"))));
-
-        for (ShardStats shardStats : client().admin().indices().prepareStats("index").clear().setRefresh(true).get().getShards()) {
-            assertThat("shard " + shardStats.getShardRouting() + " refreshed to get the timestamp range",
-                    shardStats.getStats().refresh.getTotal(), greaterThanOrEqualTo(1L));
-        }
     }
 
 }
diff --git a/...csearch/xpack/searchablesnapshots/SearchableSnapshotsCanMatchOnCoordinatorIntegTests.java b/...csearch/xpack/searchablesnapshots/SearchableSnapshotsCanMatchOnCoordinatorIntegTests.java
@@ -132,7 +132,7 @@ public void testSearchableSnapshotShardsAreSkippedWithoutQueryingAnyNodeWhenThey
             restoredIndexSettings,
             Strings.EMPTY_ARRAY,
             false,
-            MountSearchableSnapshotRequest.Storage.FULL_COPY
+            randomFrom(MountSearchableSnapshotRequest.Storage.values())
         );
         client().execute(MountSearchableSnapshotAction.INSTANCE, mountRequest).actionGet();
 
@@ -267,7 +267,7 @@ public void testQueryPhaseIsExecutedInAnAvailableNodeWhenAllShardsCanBeSkipped()
             restoredIndexSettings,
             Strings.EMPTY_ARRAY,
             false,
-            MountSearchableSnapshotRequest.Storage.FULL_COPY
+            randomFrom(MountSearchableSnapshotRequest.Storage.values())
         );
         client().execute(MountSearchableSnapshotAction.INSTANCE, mountRequest).actionGet();
         final int searchableSnapshotShardCount = indexOutsideSearchRangeShardCount;
@@ -380,7 +380,7 @@ public void testSearchableSnapshotShardsThatHaveMatchingDataAreNotSkippedOnTheCo
             restoredIndexSettings,
             Strings.EMPTY_ARRAY,
             false,
-            MountSearchableSnapshotRequest.Storage.FULL_COPY
+            randomFrom(MountSearchableSnapshotRequest.Storage.values())
         );
         client().execute(MountSearchableSnapshotAction.INSTANCE, mountRequest).actionGet();