Core: surgically removed slow scroll, because master (2.0) requires full cluster restart coming from previous versions.

src/main/java/org/elasticsearch/action/search/type/TransportSearchDfsQueryAndFetchAction.java

@@ -122,11 +122,10 @@ public class TransportSearchDfsQueryAndFetchAction extends TransportSearchTypeAc
         }
 
         private void finishHim() {
-            threadPool.executor(ThreadPool.Names.SEARCH).execute(new ActionRunnable(listener) {
+            threadPool.executor(ThreadPool.Names.SEARCH).execute(new ActionRunnable<SearchResponse>(listener) {
                 @Override
                 public void doRun() throws IOException {
-                    boolean useScroll = !useSlowScroll && request.scroll() != null;
+                    sortedShardList = searchPhaseController.sortDocs(true, queryFetchResults);
-                    sortedShardList = searchPhaseController.sortDocs(useScroll, queryFetchResults);
                     final InternalSearchResponse internalResponse = searchPhaseController.merge(sortedShardList, queryFetchResults, queryFetchResults);
                     String scrollId = null;
                     if (request.scroll() != null) {

src/main/java/org/elasticsearch/action/search/type/TransportSearchDfsQueryThenFetchAction.java

@@ -143,7 +143,7 @@ public class TransportSearchDfsQueryThenFetchAction extends TransportSearchTypeA
         }
 
         void innerExecuteFetchPhase() throws Exception {
-            boolean useScroll = !useSlowScroll && request.scroll() != null;
+            boolean useScroll = request.scroll() != null;
             sortedShardList = searchPhaseController.sortDocs(useScroll, queryResults);
             searchPhaseController.fillDocIdsToLoad(docIdsToLoad, sortedShardList);
 

src/main/java/org/elasticsearch/action/search/type/TransportSearchHelper.java

@@ -46,8 +46,8 @@ import java.util.Map;
  */
 public abstract class TransportSearchHelper {
 
-    public static ShardSearchTransportRequest internalSearchRequest(ShardRouting shardRouting, int numberOfShards, SearchRequest request, String[] filteringAliases, long nowInMillis, boolean useSlowScroll) {
+    public static ShardSearchTransportRequest internalSearchRequest(ShardRouting shardRouting, int numberOfShards, SearchRequest request, String[] filteringAliases, long nowInMillis) {
-        return new ShardSearchTransportRequest(request, shardRouting, numberOfShards, useSlowScroll, filteringAliases, nowInMillis);
+        return new ShardSearchTransportRequest(request, shardRouting, numberOfShards, filteringAliases, nowInMillis);
     }
 
     public static InternalScrollSearchRequest internalScrollSearchRequest(long id, SearchScrollRequest request) {

src/main/java/org/elasticsearch/action/search/type/TransportSearchQueryAndFetchAction.java

@@ -78,7 +78,7 @@ public class TransportSearchQueryAndFetchAction extends TransportSearchTypeActio
             threadPool.executor(ThreadPool.Names.SEARCH).execute(new ActionRunnable<SearchResponse>(listener) {
                 @Override
                 public void doRun() throws IOException {
-                    boolean useScroll = !useSlowScroll && request.scroll() != null;
+                    boolean useScroll = request.scroll() != null;
                     sortedShardList = searchPhaseController.sortDocs(useScroll, firstResults);
                     final InternalSearchResponse internalResponse = searchPhaseController.merge(sortedShardList, firstResults, firstResults);
                     String scrollId = null;

src/main/java/org/elasticsearch/action/search/type/TransportSearchQueryThenFetchAction.java

@@ -85,7 +85,7 @@ public class TransportSearchQueryThenFetchAction extends TransportSearchTypeActi
 
         @Override
         protected void moveToSecondPhase() throws Exception {
-            boolean useScroll = !useSlowScroll && request.scroll() != null;
+            boolean useScroll = request.scroll() != null;
             sortedShardList = searchPhaseController.sortDocs(useScroll, firstResults);
             searchPhaseController.fillDocIdsToLoad(docIdsToLoad, sortedShardList);
 

src/main/java/org/elasticsearch/action/search/type/TransportSearchScrollQueryAndFetchAction.java

@@ -67,12 +67,8 @@ public class TransportSearchScrollQueryAndFetchAction extends AbstractComponent
     private class AsyncAction extends AbstractAsyncAction {
 
         private final SearchScrollRequest request;
-        private volatile boolean useSlowScroll;
-
         private final ActionListener<SearchResponse> listener;
-
         private final ParsedScrollId scrollId;
-
         private final DiscoveryNodes nodes;
 
         private volatile AtomicArray<ShardSearchFailure> shardFailures;
@@ -192,7 +188,7 @@ public class TransportSearchScrollQueryAndFetchAction extends AbstractComponent
         }
 
         private void innerFinishHim() throws Exception {
-            ScoreDoc[] sortedShardList = searchPhaseController.sortDocs(!useSlowScroll, queryFetchResults);
+            ScoreDoc[] sortedShardList = searchPhaseController.sortDocs(true, queryFetchResults);
             final InternalSearchResponse internalResponse = searchPhaseController.merge(sortedShardList, queryFetchResults, queryFetchResults);
             String scrollId = null;
             if (request.scroll() != null) {

src/main/java/org/elasticsearch/action/search/type/TransportSearchScrollQueryThenFetchAction.java

@@ -85,8 +85,6 @@ public class TransportSearchScrollQueryThenFetchAction extends AbstractComponent
 
         private final AtomicInteger successfulOps;
 
-        private volatile boolean useSlowScroll;
-
         private AsyncAction(SearchScrollRequest request, ParsedScrollId scrollId, ActionListener<SearchResponse> listener) {
             this.request = request;
             this.listener = listener;
@@ -191,7 +189,7 @@ public class TransportSearchScrollQueryThenFetchAction extends AbstractComponent
         }
 
         private void executeFetchPhase() throws Exception {
-            sortedShardList = searchPhaseController.sortDocs(!useSlowScroll, queryResults);
+            sortedShardList = searchPhaseController.sortDocs(true, queryResults);
             AtomicArray<IntArrayList> docIdsToLoad = new AtomicArray<>(queryResults.length());
             searchPhaseController.fillDocIdsToLoad(docIdsToLoad, sortedShardList);
 
@@ -201,12 +199,7 @@ public class TransportSearchScrollQueryThenFetchAction extends AbstractComponent
             }
 
 
-            final ScoreDoc[] lastEmittedDocPerShard;
+            final ScoreDoc[] lastEmittedDocPerShard = searchPhaseController.getLastEmittedDocPerShard(sortedShardList, queryResults.length());
-            if (useSlowScroll) {
-                lastEmittedDocPerShard = new ScoreDoc[queryResults.length()];
-            } else {
-                lastEmittedDocPerShard = searchPhaseController.getLastEmittedDocPerShard(sortedShardList, queryResults.length());
-            }
             final AtomicInteger counter = new AtomicInteger(docIdsToLoad.asList().size());
             for (final AtomicArray.Entry<IntArrayList> entry : docIdsToLoad.asList()) {
                 IntArrayList docIds = entry.value;

src/main/java/org/elasticsearch/action/search/type/TransportSearchTypeAction.java

@@ -99,8 +99,6 @@ public abstract class TransportSearchTypeAction extends TransportAction<SearchRe
         private final Object shardFailuresMutex = new Object();
         protected volatile ScoreDoc[] sortedShardList;
 
-        protected final boolean useSlowScroll;
-
         protected BaseAsyncAction(SearchRequest request, ActionListener<SearchResponse> listener) {
             this.request = request;
             this.listener = listener;
@@ -124,7 +122,6 @@ public abstract class TransportSearchTypeAction extends TransportAction<SearchRe
             expectedTotalOps = shardsIts.totalSizeWith1ForEmpty();
 
             firstResults = new AtomicArray<>(shardsIts.size());
-            this.useSlowScroll = false;
         }
 
         public void start() {
@@ -157,7 +154,7 @@ public abstract class TransportSearchTypeAction extends TransportAction<SearchRe
                     onFirstPhaseResult(shardIndex, shard, null, shardIt, new NoShardAvailableActionException(shardIt.shardId()));
                 } else {
                     String[] filteringAliases = clusterState.metaData().filteringAliases(shard.index(), request.indices());
-                    sendExecuteFirstPhase(node, internalSearchRequest(shard, shardsIts.size(), request, filteringAliases, startTime(), useSlowScroll), new SearchServiceListener<FirstResult>() {
+                    sendExecuteFirstPhase(node, internalSearchRequest(shard, shardsIts.size(), request, filteringAliases, startTime()), new SearchServiceListener<FirstResult>() {
                         @Override
                         public void onResult(FirstResult result) {
                             onFirstPhaseResult(shardIndex, shard, result, shardIt);

src/main/java/org/elasticsearch/action/termvectors/dfs/ShardDfsOnlyRequest.java

@@ -39,7 +39,7 @@ class ShardDfsOnlyRequest extends BroadcastShardOperationRequest {
 
     ShardDfsOnlyRequest(ShardRouting shardRouting, int numberOfShards, @Nullable String[] filteringAliases, long nowInMillis, DfsOnlyRequest request) {
         super(shardRouting.shardId(), request);
-        this.shardSearchRequest = new ShardSearchTransportRequest(request.getSearchRequest(), shardRouting, numberOfShards, false,
+        this.shardSearchRequest = new ShardSearchTransportRequest(request.getSearchRequest(), shardRouting, numberOfShards,
                 filteringAliases, nowInMillis);
     }
 

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

@@ -668,16 +668,6 @@ public class PercolateContext extends SearchContext {
         throw new UnsupportedOperationException();
     }
 
-    @Override
-    public boolean useSlowScroll() {
-        throw new UnsupportedOperationException();
-    }
-
-    @Override
-    public SearchContext useSlowScroll(boolean useSlowScroll) {
-        throw new UnsupportedOperationException();
-    }
-
     @Override
     public Counter timeEstimateCounter() {
         throw new UnsupportedOperationException();

src/main/java/org/elasticsearch/search/SearchService.java

@@ -540,7 +540,6 @@ public class SearchService extends AbstractLifecycleComponent<SearchService> {
         SearchContext.setCurrent(context);
         try {
             context.scroll(request.scroll());
-            context.useSlowScroll(request.useSlowScroll());
 
             parseTemplate(request);
             parseSource(context, request.source());
@@ -722,7 +721,7 @@ public class SearchService extends AbstractLifecycleComponent<SearchService> {
      * handles this as well since the result is always size * shards for Q_A_F
      */
     private void shortcutDocIdsToLoad(SearchContext context) {
-        if (!context.useSlowScroll() && context.request().scroll() != null) {
+        if (context.request().scroll() != null) {
             TopDocs topDocs = context.queryResult().topDocs();
             int[] docIdsToLoad = new int[topDocs.scoreDocs.length];
             for (int i = 0; i < topDocs.scoreDocs.length; i++) {

src/main/java/org/elasticsearch/search/controller/SearchPhaseController.java

@@ -138,10 +138,11 @@ public class SearchPhaseController extends AbstractComponent {
     }
 
     /**
-     * @param scrollSort Whether to ignore the from and sort all hits in each shard result. Only used for scroll search
+     * @param ignoreFrom Whether to ignore the from and sort all hits in each shard result.
+     *                   Enabled only for scroll search, because that only retrieves hits of length 'size' in the query phase.
      * @param resultsArr Shard result holder
      */
-    public ScoreDoc[] sortDocs(boolean scrollSort, AtomicArray<? extends QuerySearchResultProvider> resultsArr) throws IOException {
+    public ScoreDoc[] sortDocs(boolean ignoreFrom, AtomicArray<? extends QuerySearchResultProvider> resultsArr) throws IOException {
         List<? extends AtomicArray.Entry<? extends QuerySearchResultProvider>> results = resultsArr.asList();
         if (results.isEmpty()) {
             return EMPTY_DOCS;
@@ -171,7 +172,7 @@ public class SearchPhaseController extends AbstractComponent {
             }
             if (canOptimize) {
                 int offset = result.from();
-                if (scrollSort) {
+                if (ignoreFrom) {
                     offset = 0;
                 }
                 ScoreDoc[] scoreDocs = result.topDocs().scoreDocs;
@@ -220,7 +221,7 @@ public class SearchPhaseController extends AbstractComponent {
             shardTopDocs[sortedResult.index] = topDocs;
         }
         int from = firstResult.queryResult().from();
-        if (scrollSort) {
+        if (ignoreFrom) {
             from = 0;
         }
         // TopDocs#merge can't deal with null shard TopDocs

src/main/java/org/elasticsearch/search/internal/DefaultSearchContext.java

@@ -175,8 +175,6 @@ public class DefaultSearchContext extends SearchContext {
 
     private volatile long lastAccessTime = -1;
 
-    private volatile boolean useSlowScroll;
-
     private InnerHitsContext innerHitsContext;
 
     public DefaultSearchContext(long id, ShardSearchRequest request, SearchShardTarget shardTarget,
@@ -689,16 +687,6 @@ public class DefaultSearchContext extends SearchContext {
         return mapperService().smartNameObjectMapper(name, request.types());
     }
 
-    @Override
-    public boolean useSlowScroll() {
-        return useSlowScroll;
-    }
-
-    public DefaultSearchContext useSlowScroll(boolean useSlowScroll) {
-        this.useSlowScroll = useSlowScroll;
-        return this;
-    }
-
     @Override
     public Counter timeEstimateCounter() {
         return timeEstimateCounter;

src/main/java/org/elasticsearch/search/internal/FilteredSearchContext.java

@@ -553,16 +553,6 @@ public abstract class FilteredSearchContext extends SearchContext {
         return in.smartNameObjectMapper(name);
     }
 
-    @Override
-    public boolean useSlowScroll() {
-        return in.useSlowScroll();
-    }
-
-    @Override
-    public SearchContext useSlowScroll(boolean useSlowScroll) {
-        return in.useSlowScroll(useSlowScroll);
-    }
-
     @Override
     public Counter timeEstimateCounter() {
         return in.timeEstimateCounter();

src/main/java/org/elasticsearch/search/internal/SearchContext.java

@@ -351,10 +351,6 @@ public abstract class SearchContext implements Releasable {
 
     public abstract MapperService.SmartNameObjectMapper smartNameObjectMapper(String name);
 
-    public abstract boolean useSlowScroll();
-
-    public abstract SearchContext useSlowScroll(boolean useSlowScroll);
-
     public abstract Counter timeEstimateCounter();
 
     /**

src/main/java/org/elasticsearch/search/internal/ShardSearchLocalRequest.java

@@ -19,10 +19,8 @@
 
 package org.elasticsearch.search.internal;
 
-import org.elasticsearch.Version;
 import org.elasticsearch.action.search.SearchRequest;
 import org.elasticsearch.action.search.SearchType;
-import org.elasticsearch.action.search.type.ParsedScrollId;
 import org.elasticsearch.cluster.routing.ShardRouting;
 import org.elasticsearch.common.Strings;
 import org.elasticsearch.common.bytes.BytesReference;
@@ -85,13 +83,11 @@ public class ShardSearchLocalRequest implements ShardSearchRequest {
 
     private long nowInMillis;
 
-    private boolean useSlowScroll;
-
     ShardSearchLocalRequest() {
     }
 
     ShardSearchLocalRequest(SearchRequest searchRequest, ShardRouting shardRouting, int numberOfShards,
-                            boolean useSlowScroll, String[] filteringAliases, long nowInMillis) {
+                            String[] filteringAliases, long nowInMillis) {
         this(shardRouting.shardId(), numberOfShards, searchRequest.searchType(),
                 searchRequest.source(), searchRequest.types(), searchRequest.queryCache());
 
@@ -101,7 +97,6 @@ public class ShardSearchLocalRequest implements ShardSearchRequest {
         this.templateType = searchRequest.templateType();
         this.templateParams = searchRequest.templateParams();
         this.scroll = searchRequest.scroll();
-        this.useSlowScroll = useSlowScroll;
         this.filteringAliases = filteringAliases;
         this.nowInMillis = nowInMillis;
     }
@@ -207,11 +202,6 @@ public class ShardSearchLocalRequest implements ShardSearchRequest {
         return scroll;
     }
 
-    @Override
-    public boolean useSlowScroll() {
-        return useSlowScroll;
-    }
-
     @SuppressWarnings("unchecked")
     protected void innerReadFrom(StreamInput in) throws IOException {
         index = in.readString();
@@ -235,7 +225,6 @@ public class ShardSearchLocalRequest implements ShardSearchRequest {
         if (in.readBoolean()) {
             templateParams = (Map<String, Object>) in.readGenericValue();
         }
-        useSlowScroll = in.readBoolean();
         queryCache = in.readOptionalBoolean();
     }
 
@@ -268,7 +257,6 @@ public class ShardSearchLocalRequest implements ShardSearchRequest {
         if (existTemplateParams) {
             out.writeGenericValue(templateParams);
         }
-        out.writeBoolean(useSlowScroll);
         out.writeOptionalBoolean(queryCache);
     }
 

src/main/java/org/elasticsearch/search/internal/ShardSearchRequest.java

@@ -66,15 +66,6 @@ public interface ShardSearchRequest {
 
     Scroll scroll();
 
-    /**
-     * This setting is internal and will be enabled when at least one node is on versions 1.0.x and 1.1.x to enable
-     * scrolling that those versions support.
-     *
-     * @return Whether the scrolling should use regular search and incrementing the from on each round, which can
-     * bring down nodes due to the big priority queues being generated to accommodate from + size hits for sorting.
-     */
-    boolean useSlowScroll();
-
     /**
      * Returns the cache key for this shard search request, based on its content
      */

src/main/java/org/elasticsearch/search/internal/ShardSearchTransportRequest.java

@@ -50,10 +50,9 @@ public class ShardSearchTransportRequest extends TransportRequest implements Sha
     }
 
     public ShardSearchTransportRequest(SearchRequest searchRequest, ShardRouting shardRouting, int numberOfShards,
-                                       boolean useSlowScroll, String[] filteringAliases, long nowInMillis) {
+                                       String[] filteringAliases, long nowInMillis) {
         super(searchRequest);
-        this.shardSearchLocalRequest = new ShardSearchLocalRequest(searchRequest, shardRouting, numberOfShards,
+        this.shardSearchLocalRequest = new ShardSearchLocalRequest(searchRequest, shardRouting, numberOfShards, filteringAliases, nowInMillis);
-                useSlowScroll, filteringAliases, nowInMillis);
         this.originalIndices = new OriginalIndices(searchRequest);
     }
 
@@ -153,11 +152,6 @@ public class ShardSearchTransportRequest extends TransportRequest implements Sha
         return shardSearchLocalRequest.scroll();
     }
 
-    @Override
-    public boolean useSlowScroll() {
-        return shardSearchLocalRequest.useSlowScroll();
-    }
-
     @Override
     public void readFrom(StreamInput in) throws IOException {
         super.readFrom(in);

src/main/java/org/elasticsearch/search/internal/SubSearchContext.java

@@ -345,11 +345,6 @@ public class SubSearchContext extends FilteredSearchContext {
         return searchLookup;
     }
 
-    @Override
-    public SearchContext useSlowScroll(boolean useSlowScroll) {
-        throw new UnsupportedOperationException("Not supported");
-    }
-
     @Override
     public Counter timeEstimateCounter() {
         throw new UnsupportedOperationException("Not supported");

src/main/java/org/elasticsearch/search/query/QueryPhase.java

@@ -115,7 +115,7 @@ public class QueryPhase implements SearchPhase {
                 topDocs = searchContext.scanContext().execute(searchContext);
             } else {
                 // Perhaps have a dedicated scroll phase?
-                if (!searchContext.useSlowScroll() && searchContext.request().scroll() != null) {
+                if (searchContext.request().scroll() != null) {
                     numDocs = searchContext.size();
                     ScoreDoc lastEmittedDoc = searchContext.lastEmittedDoc();
                     if (searchContext.sort() != null) {

src/test/java/org/elasticsearch/test/TestSearchContext.java

@@ -579,16 +579,6 @@ public class TestSearchContext extends SearchContext {
     public void doClose() throws ElasticsearchException {
     }
 
-    @Override
-    public boolean useSlowScroll() {
-        return false;
-    }
-
-    @Override
-    public SearchContext useSlowScroll(boolean useSlowScroll) {
-        return null;
-    }
-
     @Override
     public Counter timeEstimateCounter() {
         throw new UnsupportedOperationException();