Revert "Remove shortcutTotalHitCount optimization (#89047)" (#94159)

This reverts commit 283f8ac in the 8.7 branch (#89047).

We have found a performance regression around executing search requests with size greater than zero that hold queries that can shortcut their total hit count, like term and match_all. The previous shortcut total hit count optimization done in ES was able to shortcut those while the top score docs collector in Lucene does not support that. This can be improved further on main but for 8.7 we are going the safe path of reverting and leaving things how they were.

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

@@ -129,15 +129,21 @@ static boolean executeInternal(SearchContext searchContext) throws QueryPhaseExe
             }
 
             final LinkedList<QueryCollectorContext> collectors = new LinkedList<>();
+            // whether the chain contains a collector that filters documents
+            boolean hasFilterCollector = false;
             if (searchContext.terminateAfter() != SearchContext.DEFAULT_TERMINATE_AFTER) {
                 // add terminate_after before the filter collectors
                 // it will only be applied on documents accepted by these filter collectors
                 collectors.add(createEarlyTerminationCollectorContext(searchContext.terminateAfter()));
+                // this collector can filter documents during the collection
+                hasFilterCollector = true;
             }
             if (searchContext.parsedPostFilter() != null) {
                 // add post filters before aggregations
                 // it will only be applied to top hits
                 collectors.add(createFilteredCollectorContext(searcher, searchContext.parsedPostFilter().query()));
+                // this collector can filter documents during the collection
+                hasFilterCollector = true;
             }
             if (searchContext.queryCollectors().isEmpty() == false) {
                 // plug in additional collectors, like aggregations
@@ -146,6 +152,8 @@ static boolean executeInternal(SearchContext searchContext) throws QueryPhaseExe
             if (searchContext.minimumScore() != null) {
                 // apply the minimum score after multi collector so we filter aggs as well
                 collectors.add(createMinScoreCollectorContext(searchContext.minimumScore()));
+                // this collector can filter documents during the collection
+                hasFilterCollector = true;
             }
 
             boolean timeoutSet = scrollContext == null
@@ -168,7 +176,7 @@ static boolean executeInternal(SearchContext searchContext) throws QueryPhaseExe
             }
 
             try {
-                boolean shouldRescore = searchWithCollector(searchContext, searcher, query, collectors, timeoutSet);
+                boolean shouldRescore = searchWithCollector(searchContext, searcher, query, collectors, hasFilterCollector, timeoutSet);
                 ExecutorService executor = searchContext.indexShard().getThreadPool().executor(ThreadPool.Names.SEARCH);
                 assert executor instanceof EWMATrackingEsThreadPoolExecutor
                     || (executor instanceof EsThreadPoolExecutor == false /* in case thread pool is mocked out in tests */)
@@ -195,10 +203,11 @@ private static boolean searchWithCollector(
         ContextIndexSearcher searcher,
         Query query,
         LinkedList<QueryCollectorContext> collectors,
+        boolean hasFilterCollector,
         boolean timeoutSet
     ) throws IOException {
         // create the top docs collector last when the other collectors are known
-        final TopDocsCollectorContext topDocsFactory = createTopDocsCollectorContext(searchContext);
+        final TopDocsCollectorContext topDocsFactory = createTopDocsCollectorContext(searchContext, hasFilterCollector);
         // add the top docs collector, the first collector context in the chain
         collectors.addFirst(topDocsFactory);