Use CacheRecycler when resolving parent docs in TopChildrenQuery.

src/main/java/org/elasticsearch/common/CacheRecycler.java

@@ -44,6 +44,7 @@ public class CacheRecycler {
         shortIntHashMap.clear();
         longIntHashMap.clear();
         objectIntHashMap.clear();
+        intObjectHashMap.clear();
         objectFloatHashMap.clear();
         objectArray.clear();
         intArray.clear();
@@ -396,6 +397,34 @@ public class CacheRecycler {
         ref.add(map);
     }
 
+    // ------ TIntObjectHashMap -----
+
+    private static SoftWrapper<Queue<TIntObjectHashMap>> intObjectHashMap = new SoftWrapper<Queue<TIntObjectHashMap>>();
+
+
+    @SuppressWarnings({"unchecked"})
+    public static <T> TIntObjectHashMap<T> popIntObjectMap() {
+        Queue<TIntObjectHashMap> ref = intObjectHashMap.get();
+        if (ref == null) {
+            return new TIntObjectHashMap<T>();
+        }
+        TIntObjectHashMap<T> map = ref.poll();
+        if (map == null) {
+            return new TIntObjectHashMap<T>();
+        }
+        return map;
+    }
+
+    public static <T> void pushIntObjectMap(TIntObjectHashMap<T> map) {
+        Queue<TIntObjectHashMap> ref = intObjectHashMap.get();
+        if (ref == null) {
+            ref = ConcurrentCollections.newQueue();
+            intObjectHashMap.set(ref);
+        }
+        map.clear();
+        ref.add(map);
+    }
+
     // ------ TObjectFloatHashMap -----
 
     private static SoftWrapper<Queue<TObjectFloatHashMap>> objectFloatHashMap = new SoftWrapper<Queue<TObjectFloatHashMap>>();

src/main/java/org/elasticsearch/index/search/child/TopChildrenQuery.java

@@ -32,7 +32,10 @@ import org.elasticsearch.common.trove.ExtTHashMap;
 import org.elasticsearch.search.internal.SearchContext;
 
 import java.io.IOException;
-import java.util.*;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.Map;
+import java.util.Set;
 
 /**
  * A query that evaluates the top matching child documents (based on the score) in order to determine what
@@ -124,7 +127,7 @@ public class TopChildrenQuery extends Query implements SearchContext.Rewrite {
 
     int resolveParentDocuments(TopDocs topDocs, SearchContext context) {
         int parentHitsResolved = 0;
-        Map<Object, TIntObjectHashMap<ParentDoc>> parentDocsPerReader = new HashMap<Object, TIntObjectHashMap<ParentDoc>>();
+        ExtTHashMap<Object, TIntObjectHashMap<ParentDoc>> parentDocsPerReader = CacheRecycler.popHashMap();
         for (ScoreDoc scoreDoc : topDocs.scoreDocs) {
             int readerIndex = ReaderUtil.subIndex(scoreDoc.doc, context.searcher().getIndexReader().leaves());
             AtomicReaderContext subContext = context.searcher().getIndexReader().leaves().get(readerIndex);
@@ -146,7 +149,7 @@ public class TopChildrenQuery extends Query implements SearchContext.Rewrite {
 
                     TIntObjectHashMap<ParentDoc> readerParentDocs = parentDocsPerReader.get(indexReader.getCoreCacheKey());
                     if (readerParentDocs == null) {
-                        readerParentDocs = new TIntObjectHashMap<ParentDoc>();
+                        readerParentDocs = CacheRecycler.popIntObjectMap();
                         parentDocsPerReader.put(indexReader.getCoreCacheKey(), readerParentDocs);
                     }
 
@@ -174,8 +177,9 @@ public class TopChildrenQuery extends Query implements SearchContext.Rewrite {
             ParentDoc[] values = entry.getValue().values(new ParentDoc[entry.getValue().size()]);
             Arrays.sort(values, PARENT_DOC_COMP);
             parentDocs.put(entry.getKey(), values);
+            CacheRecycler.pushIntObjectMap(entry.getValue());
         }
-
+        CacheRecycler.pushHashMap(parentDocsPerReader);
         return parentHitsResolved;
     }
 

src/test/java/org/elasticsearch/benchmark/search/child/ChildSearchBenchmark.java

@@ -279,6 +279,27 @@ public class ChildSearchBenchmark {
         }
         System.out.println("--> top_children Query Avg: " + (totalQueryTime / QUERY_COUNT) + "ms");
 
+        System.out.println("--> Running top_children query, with match_all as child query");
+        // run parent child score query
+        for (int j = 0; j < QUERY_WARMUP; j++) {
+            SearchResponse searchResponse = client.prepareSearch(indexName).setQuery(topChildrenQuery("child", matchAllQuery())).execute().actionGet();
+            // we expect to have mismatch on hits here
+//            if (searchResponse.hits().totalHits() != COUNT) {
+//                System.err.println("mismatch on hits");
+//            }
+        }
+
+        totalQueryTime = 0;
+        for (int j = 0; j < QUERY_COUNT; j++) {
+            SearchResponse searchResponse = client.prepareSearch(indexName).setQuery(topChildrenQuery("child", matchAllQuery())).execute().actionGet();
+            // we expect to have mismatch on hits here
+//            if (searchResponse.hits().totalHits() != COUNT) {
+//                System.err.println("mismatch on hits");
+//            }
+            totalQueryTime += searchResponse.tookInMillis();
+        }
+        System.out.println("--> top_children, with match_all Query Avg: " + (totalQueryTime / QUERY_COUNT) + "ms");
+
         statsResponse = client.admin().cluster().prepareNodesStats()
                 .setJvm(true).setIndices(true).execute().actionGet();