Always set the query cache explicitely on IndexSearcher.

src/main/java/org/apache/lucene/search/postingshighlight/CustomPostingsHighlighter.java

@@ -18,9 +18,9 @@
 
 package org.apache.lucene.search.postingshighlight;
 
-import org.apache.lucene.index.LeafReaderContext;
 import org.apache.lucene.index.IndexReader;
 import org.apache.lucene.index.IndexReaderContext;
+import org.apache.lucene.index.LeafReaderContext;
 import org.apache.lucene.search.IndexSearcher;
 import org.apache.lucene.util.BytesRef;
 import org.elasticsearch.common.Strings;
@@ -91,8 +91,7 @@ public CustomPostingsHighlighter(CustomPassageFormatter passageFormatter, List<O
     /*
     Our own api to highlight a single document field, passing in the query terms, and get back our own Snippet object
      */
-    public Snippet[] highlightDoc(String field, BytesRef[] terms, IndexSearcher searcher, int docId, int maxPassages) throws IOException {
-        IndexReader reader = searcher.getIndexReader();
+    public Snippet[] highlightDoc(String field, BytesRef[] terms, IndexReader reader, int docId, int maxPassages) throws IOException {
         IndexReaderContext readerContext = reader.getContext();
         List<LeafReaderContext> leaves = readerContext.leaves();
 

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

@@ -105,6 +105,7 @@ public Weight doCreateWeight(IndexSearcher searcher, boolean needsScores) throws
 
         IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());
         indexSearcher.setSimilarity(searcher.getSimilarity());
+        indexSearcher.setQueryCache(null);
         ParentOrdCollector collector = new ParentOrdCollector(globalIfd, valueCount, parentType);
         indexSearcher.search(childQuery, collector);
 

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

@@ -155,6 +155,7 @@ public Weight doCreateWeight(IndexSearcher searcher, boolean needsScores) throws
         }
         IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());
         indexSearcher.setSimilarity(searcher.getSimilarity());
+        indexSearcher.setQueryCache(null);
 
         boolean abort = true;
         long numFoundParents;

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

@@ -94,6 +94,7 @@ public Weight doCreateWeight(IndexSearcher searcher, boolean needsScores) throws
         ParentOrdsCollector collector = new ParentOrdsCollector(globalIfd, maxOrd, parentType);
         IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());
         indexSearcher.setSimilarity(searcher.getSimilarity());
+        indexSearcher.setQueryCache(null);
         indexSearcher.search(parentQuery, collector);
 
         if (collector.parentCount() == 0) {

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

@@ -36,7 +36,6 @@
 import org.apache.lucene.search.Weight;
 import org.apache.lucene.util.Bits;
 import org.apache.lucene.util.ToStringUtils;
-import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.common.lease.Releasable;
 import org.elasticsearch.common.lease.Releasables;
 import org.elasticsearch.common.lucene.IndexCacheableQuery;
@@ -132,6 +131,7 @@ public Weight doCreateWeight(IndexSearcher searcher, boolean needsScores) throws
             collector = new ParentOrdAndScoreCollector(sc, globalIfd, parentType);
             IndexSearcher indexSearcher = new IndexSearcher(sc.searcher().getIndexReader());
             indexSearcher.setSimilarity(searcher.getSimilarity());
+            indexSearcher.setQueryCache(null);
             indexSearcher.search(parentQuery, collector);
             if (collector.parentCount() == 0) {
                 return new BooleanQuery().createWeight(searcher, needsScores);
@@ -251,12 +251,16 @@ public Scorer scorer(LeafReaderContext context, Bits acceptDocs) throws IOExcept
             if (DocIdSets.isEmpty(childrenDocSet)) {
                 return null;
             }
+            final DocIdSetIterator childIterator = childrenDocSet.iterator();
+            if (childIterator == null) {
+                return null;
+            }
             SortedDocValues bytesValues = globalIfd.load(context).getOrdinalsValues(parentType);
             if (bytesValues == null) {
                 return null;
             }
 
-            return new ChildScorer(this, parentIdxs, scores, childrenDocSet.iterator(), bytesValues);
+            return new ChildScorer(this, parentIdxs, scores, childIterator, bytesValues);
         }
 
     }

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

@@ -104,6 +104,7 @@ public Weight doCreateWeight(IndexSearcher searcher, boolean needsScores) throws
 
         IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());
         indexSearcher.setSimilarity(searcher.getSimilarity());
+        indexSearcher.setQueryCache(null);
         while (true) {
             parentDocs.clear();
             TopDocs topChildDocs = indexSearcher.search(childQuery, numChildDocs);

src/main/java/org/elasticsearch/percolator/MultiDocumentPercolatorIndex.java

@@ -71,7 +71,9 @@ public void prepare(PercolateContext context, ParsedDocument parsedDocument) {
         try {
             MultiReader mReader = new MultiReader(memoryIndices, true);
             LeafReader slowReader = SlowCompositeReaderWrapper.wrap(mReader);
-            DocSearcher docSearcher = new DocSearcher(new IndexSearcher(slowReader), rootDocMemoryIndex);
+            final IndexSearcher slowSearcher = new IndexSearcher(slowReader);
+            slowSearcher.setQueryCache(null);
+            DocSearcher docSearcher = new DocSearcher(slowSearcher, rootDocMemoryIndex);
             context.initialize(docSearcher, parsedDocument);
         } catch (IOException e) {
             throw new ElasticsearchException("Failed to create index for percolator with nested document ", e);

src/main/java/org/elasticsearch/search/fetch/FetchSubPhase.java

@@ -22,8 +22,6 @@
 import org.apache.lucene.index.LeafReader;
 import org.apache.lucene.index.LeafReaderContext;
 import org.apache.lucene.index.IndexReader;
-import org.apache.lucene.search.IndexSearcher;
-import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.search.SearchHit;
 import org.elasticsearch.search.SearchParseElement;
 import org.elasticsearch.search.internal.InternalSearchHit;
@@ -42,14 +40,12 @@ public static class HitContext {
         private LeafReaderContext readerContext;
         private int docId;
         private Map<String, Object> cache;
-        private IndexSearcher atomicIndexSearcher;
 
         public void reset(InternalSearchHit hit, LeafReaderContext context, int docId, IndexReader topLevelReader) {
             this.hit = hit;
             this.readerContext = context;
             this.docId = docId;
             this.topLevelReader = topLevelReader;
-            this.atomicIndexSearcher = null;
         }
 
         public InternalSearchHit hit() {
@@ -64,15 +60,6 @@ public LeafReaderContext readerContext() {
             return readerContext;
         }
 
-        public IndexSearcher searcher() {
-            if (atomicIndexSearcher == null) {
-                // Use the reader directly otherwise the IndexSearcher assertion will trip because it expects a top level
-                // reader context.
-                atomicIndexSearcher = new IndexSearcher(readerContext.reader());
-            }
-            return atomicIndexSearcher;
-        }
-
         public int docId() {
             return docId;
         }

src/main/java/org/elasticsearch/search/highlight/PostingsHighlighter.java

@@ -122,7 +122,7 @@ public HighlightField highlight(HighlighterContext highlighterContext) {
             //we highlight every value separately calling the highlight method multiple times, only if we need to have back a snippet per value (whole value)
             int values = mergeValues ? 1 : textsToHighlight.size();
             for (int i = 0; i < values; i++) {
-                Snippet[] fieldSnippets = highlighter.highlightDoc(fieldMapper.names().indexName(), mapperHighlighterEntry.filteredQueryTerms, hitContext.searcher(), hitContext.docId(), numberOfFragments);
+                Snippet[] fieldSnippets = highlighter.highlightDoc(fieldMapper.names().indexName(), mapperHighlighterEntry.filteredQueryTerms, hitContext.reader(), hitContext.docId(), numberOfFragments);
                 if (fieldSnippets != null) {
                     for (Snippet fieldSnippet : fieldSnippets) {
                         if (Strings.hasText(fieldSnippet.getText())) {

src/main/java/org/elasticsearch/search/lookup/LeafIndexLookup.java

@@ -18,12 +18,12 @@
  */
 package org.elasticsearch.search.lookup;
 
-import org.apache.lucene.index.CompositeReader;
 import org.apache.lucene.index.Fields;
 import org.apache.lucene.index.IndexReader;
 import org.apache.lucene.index.IndexReaderContext;
 import org.apache.lucene.index.LeafReader;
 import org.apache.lucene.index.LeafReaderContext;
+import org.apache.lucene.index.ReaderUtil;
 import org.apache.lucene.search.IndexSearcher;
 import org.elasticsearch.ElasticsearchException;
 import org.elasticsearch.common.util.MinimalMap;
@@ -40,14 +40,11 @@ public class LeafIndexLookup extends MinimalMap<String, IndexField> {
 
     // The parent reader from which we can get proper field and term
     // statistics
-    private final CompositeReader parentReader;
+    private final IndexReader parentReader;
 
     // we need this later to get the field and term statistics of the shard
     private final IndexSearcher indexSearcher;
 
-    // we need this later to get the term statistics of the shard
-    private final IndexReaderContext indexReaderContext;
-
     // current docId
     private int docId = -1;
 
@@ -90,15 +87,9 @@ public int numDeletedDocs() {
 
     public LeafIndexLookup(LeafReaderContext ctx) {
         reader = ctx.reader();
-        if (ctx.parent != null) {
-            parentReader = ctx.parent.reader();
-            indexSearcher = new IndexSearcher(parentReader);
-            indexReaderContext = ctx.parent;
-        } else {
-            parentReader = null;
-            indexSearcher = null;
-            indexReaderContext = null;
-        }
+        parentReader = ReaderUtil.getTopLevelContext(ctx).reader();
+        indexSearcher = new IndexSearcher(parentReader);
+        indexSearcher.setQueryCache(null);
     }
 
     public void setDocument(int docId) {
@@ -175,13 +166,10 @@ public IndexReader getParentReader() {
     }
 
     public IndexSearcher getIndexSearcher() {
-        if (indexSearcher == null) {
-            return new IndexSearcher(reader);
-        }
         return indexSearcher;
     }
 
     public IndexReaderContext getReaderContext() {
-        return indexReaderContext;
+        return getParentReader().getContext();
     }
 }

src/test/java/org/apache/lucene/search/postingshighlight/CustomPostingsHighlighterTests.java

@@ -82,39 +82,39 @@ public void testDiscreteHighlightingPerValue() throws Exception {
         Query query = new TermQuery(new Term("body", "highlighting"));
         BytesRef[] queryTerms = filterTerms(extractTerms(searcher, query), "body", true);
 
-        TopDocs topDocs = searcher.search(query, null, 10, Sort.INDEXORDER);
+        TopDocs topDocs = searcher.search(query, 10, Sort.INDEXORDER);
         assertThat(topDocs.totalHits, equalTo(1));
         int docId = topDocs.scoreDocs[0].doc;
 
         //highlighting per value, considering whole values (simulating number_of_fragments=0)
         CustomPostingsHighlighter highlighter = new CustomPostingsHighlighter(new CustomPassageFormatter("<b>", "</b>", new DefaultEncoder()), fieldValues, false, Integer.MAX_VALUE - 1, 0);
         highlighter.setBreakIterator(new WholeBreakIterator());
 
-        Snippet[] snippets = highlighter.highlightDoc("body", queryTerms, searcher, docId, 5);
+        Snippet[] snippets = highlighter.highlightDoc("body", queryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(1));
         assertThat(snippets[0].getText(), equalTo("This is a test. Just a test <b>highlighting</b> from postings highlighter."));
 
-        snippets = highlighter.highlightDoc("body", queryTerms, searcher, docId, 5);
+        snippets = highlighter.highlightDoc("body", queryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(1));
         assertThat(snippets[0].getText(), equalTo("This is the second value to perform <b>highlighting</b> on."));
 
-        snippets = highlighter.highlightDoc("body", queryTerms, searcher, docId, 5);
+        snippets = highlighter.highlightDoc("body", queryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(1));
         assertThat(snippets[0].getText(), equalTo("This is the third value to test <b>highlighting</b> with postings."));
 
 
         //let's try without whole break iterator as well, to prove that highlighting works the same when working per value (not optimized though)
         highlighter = new CustomPostingsHighlighter(new CustomPassageFormatter("<b>", "</b>", new DefaultEncoder()), fieldValues, false, Integer.MAX_VALUE - 1, 0);
 
-        snippets = highlighter.highlightDoc("body", queryTerms, searcher, docId, 5);
+        snippets = highlighter.highlightDoc("body", queryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(1));
         assertThat(snippets[0].getText(), equalTo("Just a test <b>highlighting</b> from postings highlighter."));
 
-        snippets = highlighter.highlightDoc("body", queryTerms, searcher, docId, 5);
+        snippets = highlighter.highlightDoc("body", queryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(1));
         assertThat(snippets[0].getText(), equalTo("This is the second value to perform <b>highlighting</b> on."));
 
-        snippets = highlighter.highlightDoc("body", queryTerms, searcher, docId, 5);
+        snippets = highlighter.highlightDoc("body", queryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(1));
         assertThat(snippets[0].getText(), equalTo("This is the third value to test <b>highlighting</b> with postings."));
 
@@ -177,7 +177,7 @@ public void testDiscreteHighlightingScoring() throws Exception {
         Query query = new TermQuery(new Term("body", "highlighting"));
         BytesRef[] queryTerms = filterTerms(extractTerms(searcher, query), "body", true);
 
-        TopDocs topDocs = searcher.search(query, null, 10, Sort.INDEXORDER);
+        TopDocs topDocs = searcher.search(query, 10, Sort.INDEXORDER);
         assertThat(topDocs.totalHits, equalTo(1));
 
         int docId = topDocs.scoreDocs[0].doc;
@@ -190,7 +190,7 @@ public void testDiscreteHighlightingScoring() throws Exception {
 
         boolean mergeValues = true;
         CustomPostingsHighlighter highlighter = new CustomPostingsHighlighter(new CustomPassageFormatter("<b>", "</b>", new DefaultEncoder()), fieldValues, mergeValues, Integer.MAX_VALUE-1, 0);
-        Snippet[] snippets = highlighter.highlightDoc("body", queryTerms, searcher, docId, 5);
+        Snippet[] snippets = highlighter.highlightDoc("body", queryTerms, ir, docId, 5);
 
         assertThat(snippets.length, equalTo(4));
 
@@ -205,7 +205,7 @@ public void testDiscreteHighlightingScoring() throws Exception {
         highlighter = new CustomPostingsHighlighter(new CustomPassageFormatter("<b>", "</b>", new DefaultEncoder()), fieldValues, mergeValues, Integer.MAX_VALUE-1, 0);
         List<Snippet> snippets2 = new ArrayList<>();
         for (int i = 0; i < fieldValues.size(); i++) {
-            snippets2.addAll(Arrays.asList(highlighter.highlightDoc("body", queryTerms, searcher, docId, 5)));
+            snippets2.addAll(Arrays.asList(highlighter.highlightDoc("body", queryTerms, ir, docId, 5)));
         }
 
         assertThat(snippets2.size(), equalTo(4));
@@ -292,7 +292,7 @@ public void testMergeValuesScoring() throws Exception {
         Query query = new TermQuery(new Term("body", "highlighting"));
         BytesRef[] queryTerms = filterTerms(extractTerms(searcher, query), "body", true);
 
-        TopDocs topDocs = searcher.search(query, null, 10, Sort.INDEXORDER);
+        TopDocs topDocs = searcher.search(query, 10, Sort.INDEXORDER);
         assertThat(topDocs.totalHits, equalTo(1));
 
         int docId = topDocs.scoreDocs[0].doc;
@@ -305,7 +305,7 @@ public void testMergeValuesScoring() throws Exception {
 
         boolean mergeValues = true;
         CustomPostingsHighlighter highlighter = new CustomPostingsHighlighter(new CustomPassageFormatter("<b>", "</b>", new DefaultEncoder()), fieldValues, mergeValues, Integer.MAX_VALUE-1, 0);
-        Snippet[] snippets = highlighter.highlightDoc("body", queryTerms, searcher, docId, 5);
+        Snippet[] snippets = highlighter.highlightDoc("body", queryTerms, ir, docId, 5);
 
         assertThat(snippets.length, equalTo(4));
 
@@ -379,7 +379,7 @@ public void testRequireFieldMatch() throws Exception {
         Query query = new TermQuery(new Term("none", "highlighting"));
         IndexSearcher searcher = newSearcher(ir);
         SortedSet<Term> queryTerms = extractTerms(searcher, query);
-        TopDocs topDocs = searcher.search(query, null, 10, Sort.INDEXORDER);
+        TopDocs topDocs = searcher.search(query, 10, Sort.INDEXORDER);
         assertThat(topDocs.totalHits, equalTo(1));
         int docId = topDocs.scoreDocs[0].doc;
 
@@ -392,15 +392,15 @@ public void testRequireFieldMatch() throws Exception {
         //no snippets with simulated require field match (we filter the terms ourselves)
         boolean requireFieldMatch = true;
         BytesRef[] filteredQueryTerms = filterTerms(queryTerms, "body", requireFieldMatch);
-        Snippet[] snippets = highlighter.highlightDoc("body", filteredQueryTerms, searcher, docId, 5);
+        Snippet[] snippets = highlighter.highlightDoc("body", filteredQueryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(0));
 
 
         highlighter = new CustomPostingsHighlighter(passageFormatter, values, true, Integer.MAX_VALUE - 1, 0);
         //one snippet without require field match, just passing in the query terms with no filtering on our side
         requireFieldMatch = false;
         filteredQueryTerms = filterTerms(queryTerms, "body", requireFieldMatch);
-        snippets = highlighter.highlightDoc("body", filteredQueryTerms, searcher, docId, 5);
+        snippets = highlighter.highlightDoc("body", filteredQueryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(1));
         assertThat(snippets[0].getText(), equalTo("Just a test <b>highlighting</b> from postings."));
 
@@ -435,7 +435,7 @@ public void testNoMatchSize() throws Exception {
 
         IndexSearcher searcher = newSearcher(ir);
         SortedSet<Term> queryTerms = extractTerms(searcher, query);
-        TopDocs topDocs = searcher.search(query, null, 10, Sort.INDEXORDER);
+        TopDocs topDocs = searcher.search(query, 10, Sort.INDEXORDER);
         assertThat(topDocs.totalHits, equalTo(1));
         int docId = topDocs.scoreDocs[0].doc;
 
@@ -446,11 +446,11 @@ public void testNoMatchSize() throws Exception {
         CustomPassageFormatter passageFormatter = new CustomPassageFormatter("<b>", "</b>", new DefaultEncoder());
 
         CustomPostingsHighlighter highlighter = new CustomPostingsHighlighter(passageFormatter, values, true, Integer.MAX_VALUE - 1, 0);
-        Snippet[] snippets = highlighter.highlightDoc("body", filteredQueryTerms, searcher, docId, 5);
+        Snippet[] snippets = highlighter.highlightDoc("body", filteredQueryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(0));
 
         highlighter = new CustomPostingsHighlighter(passageFormatter, values, true, Integer.MAX_VALUE - 1, scaledRandomIntBetween(1, 10));
-        snippets = highlighter.highlightDoc("body", filteredQueryTerms, searcher, docId, 5);
+        snippets = highlighter.highlightDoc("body", filteredQueryTerms, ir, docId, 5);
         assertThat(snippets.length, equalTo(1));
         assertThat(snippets[0].getText(), equalTo("This is a test."));