Revert "SERVER-40755 Expose statistics which indicate how many collection scans have executed"

This reverts commit a4ef14ef41f0700ef07e5b57b0345d2396a44604.

24 files changed, 19 insertions, 176 deletions

diff --git a/src/mongo/db/SConscript b/src/mongo/db/SConscript
index 61ee62fece7..39cce30206b 100644
--- a/src/mongo/db/SConscript
+++ b/src/mongo/db/SConscript
@@ -455,7 +455,6 @@ env.Library(
     ],
     LIBDEPS=[
         '$BUILD_DIR/mongo/base',
-        '$BUILD_DIR/mongo/db/commands/server_status_core',
     ],
 )
 
diff --git a/src/mongo/db/catalog/collection_info_cache.h b/src/mongo/db/catalog/collection_info_cache.h
index 8ae84fb3eec..254df201721 100644
--- a/src/mongo/db/catalog/collection_info_cache.h
+++ b/src/mongo/db/catalog/collection_info_cache.h
@@ -31,7 +31,6 @@
 
 #include "mongo/db/collection_index_usage_tracker.h"
 #include "mongo/db/query/plan_cache.h"
-#include "mongo/db/query/plan_summary_stats.h"
 #include "mongo/db/query/query_settings.h"
 #include "mongo/db/update_index_data.h"
 
@@ -78,12 +77,6 @@ public:
     virtual CollectionIndexUsageMap getIndexUsageStats() const = 0;
 
     /**
-     * Returns a struct containing information on the number of collection scans that have been
-     * performed.
-     */
-    virtual CollectionIndexUsageTracker::CollectionScanStats getCollectionScanStats() const = 0;
-
-    /**
      * Register a newly-created index with the cache.  Must be called whenever an index is
      * built on the associated collection.
      *
@@ -106,12 +99,10 @@ public:
 
     /**
      * Signal to the cache that a query operation has completed.  'indexesUsed' should list the
-     * set of indexes used by the winning plan, if any. 'summaryStats.collectionScans' and
-     * 'summaryStats.collectionScansNonTailable' should be the number of collections scans and
-     * non-tailable collection scans that occured while executing the winning plan.
+     * set of indexes used by the winning plan, if any.
      */
     virtual void notifyOfQuery(OperationContext* const opCtx,
-                               const PlanSummaryStats& summaryStats) = 0;
+                               const std::set<std::string>& indexesUsed) = 0;
 
     virtual void setNs(NamespaceString ns) = 0;
 };
diff --git a/src/mongo/db/catalog/collection_info_cache_impl.cpp b/src/mongo/db/catalog/collection_info_cache_impl.cpp
index b79def3cd04..bf4866b750a 100644
--- a/src/mongo/db/catalog/collection_info_cache_impl.cpp
+++ b/src/mongo/db/catalog/collection_info_cache_impl.cpp
@@ -38,7 +38,6 @@
 #include "mongo/db/catalog/collection.h"
 #include "mongo/db/catalog/index_catalog.h"
 #include "mongo/db/concurrency/d_concurrency.h"
-#include "mongo/db/curop_metrics.h"
 #include "mongo/db/fts/fts_spec.h"
 #include "mongo/db/index/index_descriptor.h"
 #include "mongo/db/index/wildcard_access_method.h"
@@ -163,11 +162,7 @@ void CollectionInfoCacheImpl::computeIndexKeys(OperationContext* opCtx) {
 }
 
 void CollectionInfoCacheImpl::notifyOfQuery(OperationContext* opCtx,
-                                            const PlanSummaryStats& summaryStats) {
-    _indexUsageTracker.recordCollectionScans(summaryStats.collectionScans);
-    _indexUsageTracker.recordCollectionScansNonTailable(summaryStats.collectionScansNonTailable);
-
-    const auto& indexesUsed = summaryStats.indexesUsed;
+                                            const std::set<std::string>& indexesUsed) {
     // Record indexes used to fulfill query.
     for (auto it = indexesUsed.begin(); it != indexesUsed.end(); ++it) {
         // This index should still exist, since the PlanExecutor would have been killed if the
@@ -268,9 +263,4 @@ void CollectionInfoCacheImpl::setNs(NamespaceString ns) {
     }
 }
 
-CollectionIndexUsageTracker::CollectionScanStats CollectionInfoCacheImpl::getCollectionScanStats()
-    const {
-    return _indexUsageTracker.getCollectionScanStats();
-}
-
 }  // namespace mongo
diff --git a/src/mongo/db/catalog/collection_info_cache_impl.h b/src/mongo/db/catalog/collection_info_cache_impl.h
index cf66d8e2e99..ff6566f36e5 100644
--- a/src/mongo/db/catalog/collection_info_cache_impl.h
+++ b/src/mongo/db/catalog/collection_info_cache_impl.h
@@ -76,8 +76,6 @@ public:
      */
     CollectionIndexUsageMap getIndexUsageStats() const;
 
-    CollectionIndexUsageTracker::CollectionScanStats getCollectionScanStats() const override;
-
     /**
      * Builds internal cache state based on the current state of the Collection's IndexCatalog
      */
@@ -104,7 +102,11 @@ public:
      */
     void clearQueryCache();
 
-    void notifyOfQuery(OperationContext* opCtx, const PlanSummaryStats& summaryStats);
+    /**
+     * Signal to the cache that a query operation has completed.  'indexesUsed' should list the
+     * set of indexes used by the winning plan, if any.
+     */
+    void notifyOfQuery(OperationContext* opCtx, const std::set<std::string>& indexesUsed);
 
     void setNs(NamespaceString ns) override;
 
diff --git a/src/mongo/db/collection_index_usage_tracker.cpp b/src/mongo/db/collection_index_usage_tracker.cpp
index 3f78b3c406a..dc0941ff4c8 100644
--- a/src/mongo/db/collection_index_usage_tracker.cpp
+++ b/src/mongo/db/collection_index_usage_tracker.cpp
@@ -31,23 +31,12 @@
 
 #include "mongo/platform/basic.h"
 
-#include "mongo/base/counter.h"
 #include "mongo/db/collection_index_usage_tracker.h"
-#include "mongo/db/commands/server_status_metric.h"
 #include "mongo/util/assert_util.h"
 #include "mongo/util/clock_source.h"
 #include "mongo/util/log.h"
 
 namespace mongo {
-namespace {
-Counter64 collectionScansCounter;
-Counter64 collectionScansNonTailableCounter;
-
-ServerStatusMetricField<Counter64> displayCollectionScans("queryExecutor.collectionScans.total",
-                                                          &collectionScansCounter);
-ServerStatusMetricField<Counter64> displayCollectionScansNonTailable(
-    "queryExecutor.collectionScans.nonTailable", &collectionScansNonTailableCounter);
-}
 
 CollectionIndexUsageTracker::CollectionIndexUsageTracker(ClockSource* clockSource)
     : _clockSource(clockSource) {
@@ -61,17 +50,6 @@ void CollectionIndexUsageTracker::recordIndexAccess(StringData indexName) {
     _indexUsageMap[indexName].accesses.fetchAndAdd(1);
 }
 
-void CollectionIndexUsageTracker::recordCollectionScans(unsigned long long collectionScans) {
-    _collectionScans.fetchAndAdd(collectionScans);
-    collectionScansCounter.increment(collectionScans);
-}
-
-void CollectionIndexUsageTracker::recordCollectionScansNonTailable(
-    unsigned long long collectionScansNonTailable) {
-    _collectionScansNonTailable.fetchAndAdd(collectionScansNonTailable);
-    collectionScansNonTailableCounter.increment(collectionScansNonTailable);
-}
-
 void CollectionIndexUsageTracker::registerIndex(StringData indexName, const BSONObj& indexKey) {
     invariant(!indexName.empty());
     dassert(_indexUsageMap.find(indexName) == _indexUsageMap.end());
@@ -90,8 +68,4 @@ CollectionIndexUsageMap CollectionIndexUsageTracker::getUsageStats() const {
     return _indexUsageMap;
 }
 
-CollectionIndexUsageTracker::CollectionScanStats
-CollectionIndexUsageTracker::getCollectionScanStats() const {
-    return {_collectionScans.load(), _collectionScansNonTailable.load()};
-}
 }  // namespace mongo
diff --git a/src/mongo/db/collection_index_usage_tracker.h b/src/mongo/db/collection_index_usage_tracker.h
index b70d7887723..62c3b610f41 100644
--- a/src/mongo/db/collection_index_usage_tracker.h
+++ b/src/mongo/db/collection_index_usage_tracker.h
@@ -44,9 +44,6 @@ class ClockSource;
  * considered "used" when it appears as part of a winning plan for an operation that uses the
  * query system.
  *
- * It also tracks non-usage of indexes. I.e. it collects information about collection scans that
- * occur on a collection.
- *
  * Indexes must be registered and deregistered on creation/destruction.
  */
 class CollectionIndexUsageTracker {
@@ -54,11 +51,6 @@ class CollectionIndexUsageTracker {
     CollectionIndexUsageTracker& operator=(const CollectionIndexUsageTracker&) = delete;
 
 public:
-    struct CollectionScanStats {
-        unsigned long long collectionScans{0};
-        unsigned long long collectionScansNonTailable{0};
-    };
-
     struct IndexUsageStats {
         IndexUsageStats() = default;
         explicit IndexUsageStats(Date_t now, const BSONObj& key)
@@ -119,15 +111,6 @@ public:
      */
     StringMap<CollectionIndexUsageTracker::IndexUsageStats> getUsageStats() const;
 
-    /**
-     * Get the current state of the usage of collection scans. This struct will only include
-     * information about the collection scans that have occured at the time of calling.
-     */
-    CollectionScanStats getCollectionScanStats() const;
-
-    void recordCollectionScans(unsigned long long collectionScans);
-    void recordCollectionScansNonTailable(unsigned long long collectionScansNonTailable);
-
 private:
     // Map from index name to usage statistics.
     StringMap<CollectionIndexUsageTracker::IndexUsageStats> _indexUsageMap;
@@ -135,10 +118,8 @@ private:
     // Clock source. Used when the 'trackerStartTime' time for an IndexUsageStats object needs to
     // be set.
     ClockSource* _clockSource;
-
-    AtomicWord<unsigned long long> _collectionScans{0};
-    AtomicWord<unsigned long long> _collectionScansNonTailable{0};
 };
 
 typedef StringMap<CollectionIndexUsageTracker::IndexUsageStats> CollectionIndexUsageMap;
+
 }  // namespace mongo
diff --git a/src/mongo/db/commands/count_cmd.cpp b/src/mongo/db/commands/count_cmd.cpp
index 545afc0c174..82a6408b6e8 100644
--- a/src/mongo/db/commands/count_cmd.cpp
+++ b/src/mongo/db/commands/count_cmd.cpp
@@ -243,7 +243,7 @@ public:
         PlanSummaryStats summaryStats;
         Explain::getSummaryStats(*exec, &summaryStats);
         if (collection) {
-            collection->infoCache()->notifyOfQuery(opCtx, summaryStats);
+            collection->infoCache()->notifyOfQuery(opCtx, summaryStats.indexesUsed);
         }
         curOp->debug().setPlanSummaryMetrics(summaryStats);
 
diff --git a/src/mongo/db/commands/distinct.cpp b/src/mongo/db/commands/distinct.cpp
index ac156b32c30..eee399d134d 100644
--- a/src/mongo/db/commands/distinct.cpp
+++ b/src/mongo/db/commands/distinct.cpp
@@ -285,7 +285,7 @@ public:
         PlanSummaryStats stats;
         Explain::getSummaryStats(*executor.getValue(), &stats);
         if (collection) {
-            collection->infoCache()->notifyOfQuery(opCtx, stats);
+            collection->infoCache()->notifyOfQuery(opCtx, stats.indexesUsed);
         }
         curOp->debug().setPlanSummaryMetrics(stats);
 
diff --git a/src/mongo/db/commands/find_and_modify.cpp b/src/mongo/db/commands/find_and_modify.cpp
index ee2a87987d2..a60dfa214e0 100644
--- a/src/mongo/db/commands/find_and_modify.cpp
+++ b/src/mongo/db/commands/find_and_modify.cpp
@@ -396,7 +396,7 @@ public:
                 PlanSummaryStats summaryStats;
                 Explain::getSummaryStats(*exec, &summaryStats);
                 if (collection) {
-                    collection->infoCache()->notifyOfQuery(opCtx, summaryStats);
+                    collection->infoCache()->notifyOfQuery(opCtx, summaryStats.indexesUsed);
                 }
                 opDebug->setPlanSummaryMetrics(summaryStats);
 
@@ -494,7 +494,7 @@ public:
                 PlanSummaryStats summaryStats;
                 Explain::getSummaryStats(*exec, &summaryStats);
                 if (collection) {
-                    collection->infoCache()->notifyOfQuery(opCtx, summaryStats);
+                    collection->infoCache()->notifyOfQuery(opCtx, summaryStats.indexesUsed);
                 }
                 UpdateStage::recordUpdateStatsInOpDebug(UpdateStage::getUpdateStats(exec.get()),
                                                         opDebug);
diff --git a/src/mongo/db/commands/mr.cpp b/src/mongo/db/commands/mr.cpp
index 74ec1dbfdbe..45f0fd6fbed 100644
--- a/src/mongo/db/commands/mr.cpp
+++ b/src/mongo/db/commands/mr.cpp
@@ -1563,7 +1563,7 @@ bool runMapReduce(OperationContext* opCtx,
             // TODO SERVER-23261: Confirm whether this is the correct place to gather all
             // metrics. There is no harm adding here for the time being.
             curOp->debug().setPlanSummaryMetrics(stats);
-            scopedAutoColl->getCollection()->infoCache()->notifyOfQuery(opCtx, stats);
+            scopedAutoColl->getCollection()->infoCache()->notifyOfQuery(opCtx, stats.indexesUsed);
 
             if (curOp->shouldDBProfile()) {
                 BSONObjBuilder execStatsBob;
diff --git a/src/mongo/db/commands/run_aggregate.cpp b/src/mongo/db/commands/run_aggregate.cpp
index ab63dec4dbe..1a62a4b0b34 100644
--- a/src/mongo/db/commands/run_aggregate.cpp
+++ b/src/mongo/db/commands/run_aggregate.cpp
@@ -786,7 +786,7 @@ Status runAggregate(OperationContext* opCtx,
         // For an optimized away pipeline, signal the cache that a query operation has completed.
         // For normal pipelines this is done in DocumentSourceCursor.
         if (ctx && ctx->getCollection()) {
-            ctx->getCollection()->infoCache()->notifyOfQuery(opCtx, stats);
+            ctx->getCollection()->infoCache()->notifyOfQuery(opCtx, stats.indexesUsed);
         }
     }
 
diff --git a/src/mongo/db/exec/collection_scan.cpp b/src/mongo/db/exec/collection_scan.cpp
index e06493b39eb..6a1e64dd30f 100644
--- a/src/mongo/db/exec/collection_scan.cpp
+++ b/src/mongo/db/exec/collection_scan.cpp
@@ -67,7 +67,6 @@ CollectionScan::CollectionScan(OperationContext* opCtx,
     // Explain reports the direction of the collection scan.
     _specificStats.direction = params.direction;
     _specificStats.maxTs = params.maxTs;
-    _specificStats.tailable = params.tailable;
     invariant(!_params.shouldTrackLatestOplogTimestamp || collection->ns().isOplog());
 
     if (params.maxTs) {
diff --git a/src/mongo/db/exec/plan_stats.h b/src/mongo/db/exec/plan_stats.h
index 08d623ffc44..e85a508979f 100644
--- a/src/mongo/db/exec/plan_stats.h
+++ b/src/mongo/db/exec/plan_stats.h
@@ -198,8 +198,6 @@ struct CollectionScanStats : public SpecificStats {
     // backwards.
     int direction;
 
-    bool tailable{false};
-
     // If present, indicates that the collection scan will stop and return EOF the first time it
     // sees a document that does not pass the filter and has a "ts" Timestamp field greater than
     // 'maxTs'.
diff --git a/src/mongo/db/ops/write_ops_exec.cpp b/src/mongo/db/ops/write_ops_exec.cpp
index 954479180c3..5176503ef73 100644
--- a/src/mongo/db/ops/write_ops_exec.cpp
+++ b/src/mongo/db/ops/write_ops_exec.cpp
@@ -651,7 +651,7 @@ static SingleWriteResult performSingleUpdateOp(OperationContext* opCtx,
     PlanSummaryStats summary;
     Explain::getSummaryStats(*exec, &summary);
     if (collection->getCollection()) {
-        collection->getCollection()->infoCache()->notifyOfQuery(opCtx, summary);
+        collection->getCollection()->infoCache()->notifyOfQuery(opCtx, summary.indexesUsed);
     }
 
     if (curOp.shouldDBProfile()) {
@@ -892,7 +892,7 @@ static SingleWriteResult performSingleDeleteOp(OperationContext* opCtx,
     PlanSummaryStats summary;
     Explain::getSummaryStats(*exec, &summary);
     if (collection.getCollection()) {
-        collection.getCollection()->infoCache()->notifyOfQuery(opCtx, summary);
+        collection.getCollection()->infoCache()->notifyOfQuery(opCtx, summary.indexesUsed);
     }
     curOp.debug().setPlanSummaryMetrics(summary);
 
diff --git a/src/mongo/db/pipeline/document_source_coll_stats.cpp b/src/mongo/db/pipeline/document_source_coll_stats.cpp
index a02a6018231..df6063dad52 100644
--- a/src/mongo/db/pipeline/document_source_coll_stats.cpp
+++ b/src/mongo/db/pipeline/document_source_coll_stats.cpp
@@ -85,17 +85,6 @@ intrusive_ptr<DocumentSource> DocumentSourceCollStats::createFromBson(
                                   << " of type "
                                   << typeName(elem.type()),
                     elem.type() == BSONType::Object);
-        } else if ("queryExecStats" == fieldName) {
-            uassert(31141,
-                    str::stream() << "queryExecStats argument must be an empty object, but got "
-                                  << elem
-                                  << " of type "
-                                  << typeName(elem.type()),
-                    elem.type() == BSONType::Object);
-            uassert(31170,
-                    str::stream() << "queryExecStats argument must be an empty object, but got "
-                                  << elem,
-                    elem.embeddedObject().isEmpty());
         } else {
             uasserted(40168, str::stream() << "unrecognized option to $collStats: " << fieldName);
         }
@@ -160,16 +149,6 @@ DocumentSource::GetNextResult DocumentSourceCollStats::getNext() {
         }
     }
 
-    if (_collStatsSpec.hasField("queryExecStats")) {
-        Status status = pExpCtx->mongoProcessInterface->appendQueryExecStats(
-            pExpCtx->opCtx, pExpCtx->ns, &builder);
-        if (!status.isOK()) {
-            uasserted(31142,
-                      str::stream() << "Unable to retrieve queryExecStats in $collStats stage: "
-                                    << status.reason());
-        }
-    }
-
     return {Document(builder.obj())};
 }
 
diff --git a/src/mongo/db/pipeline/document_source_cursor.cpp b/src/mongo/db/pipeline/document_source_cursor.cpp
index f4e53f20d16..1d971d188a8 100644
--- a/src/mongo/db/pipeline/document_source_cursor.cpp
+++ b/src/mongo/db/pipeline/document_source_cursor.cpp
@@ -322,7 +322,7 @@ DocumentSourceCursor::DocumentSourceCursor(
     }
 
     if (collection) {
-        collection->infoCache()->notifyOfQuery(pExpCtx->opCtx, _planSummaryStats);
+        collection->infoCache()->notifyOfQuery(pExpCtx->opCtx, _planSummaryStats.indexesUsed);
     }
 }
 
diff --git a/src/mongo/db/pipeline/mongo_process_interface.h b/src/mongo/db/pipeline/mongo_process_interface.h
index 4e4165d29f3..ae7e707e3e9 100644
--- a/src/mongo/db/pipeline/mongo_process_interface.h
+++ b/src/mongo/db/pipeline/mongo_process_interface.h
@@ -195,12 +195,6 @@ public:
     virtual Status appendRecordCount(OperationContext* opCtx,
                                      const NamespaceString& nss,
                                      BSONObjBuilder* builder) const = 0;
-    /**
-     * Appends the exec stats for the collection 'nss' to 'builder'.
-     */
-    virtual Status appendQueryExecStats(OperationContext* opCtx,
-                                        const NamespaceString& nss,
-                                        BSONObjBuilder* builder) const = 0;
 
     /**
      * Gets the collection options for the collection given by 'nss'. Throws
diff --git a/src/mongo/db/pipeline/mongos_process_interface.h b/src/mongo/db/pipeline/mongos_process_interface.h
index fcfe82d6321..39c69b2daf7 100644
--- a/src/mongo/db/pipeline/mongos_process_interface.h
+++ b/src/mongo/db/pipeline/mongos_process_interface.h
@@ -144,12 +144,6 @@ public:
         MONGO_UNREACHABLE;
     }
 
-    Status appendQueryExecStats(OperationContext* opCtx,
-                                const NamespaceString& nss,
-                                BSONObjBuilder* builder) const final {
-        MONGO_UNREACHABLE;
-    }
-
     BSONObj getCollectionOptions(const NamespaceString& nss) final {
         MONGO_UNREACHABLE;
     }
diff --git a/src/mongo/db/pipeline/process_interface_standalone.cpp b/src/mongo/db/pipeline/process_interface_standalone.cpp
index 6e13e969ac4..d7a51028503 100644
--- a/src/mongo/db/pipeline/process_interface_standalone.cpp
+++ b/src/mongo/db/pipeline/process_interface_standalone.cpp
@@ -282,39 +282,6 @@ Status MongoInterfaceStandalone::appendRecordCount(OperationContext* opCtx,
     return appendCollectionRecordCount(opCtx, nss, builder);
 }
 
-Status MongoInterfaceStandalone::appendQueryExecStats(OperationContext* opCtx,
-                                                      const NamespaceString& nss,
-                                                      BSONObjBuilder* builder) const {
-    AutoGetCollectionForReadCommand autoColl(opCtx, nss);
-
-    if (!autoColl.getDb()) {
-        return {ErrorCodes::NamespaceNotFound,
-                str::stream() << "Database [" << nss.db().toString() << "] not found."};
-    }
-
-    Collection* collection = autoColl.getCollection();
-
-    if (!collection) {
-        return {ErrorCodes::NamespaceNotFound,
-                str::stream() << "Collection [" << nss.toString() << "] not found."};
-    }
-
-    auto collectionScanStats = collection->infoCache()->getCollectionScanStats();
-
-    dassert(collectionScanStats.collectionScans <=
-            static_cast<unsigned long long>(std::numeric_limits<long long>::max()));
-    dassert(collectionScanStats.collectionScansNonTailable <=
-            static_cast<unsigned long long>(std::numeric_limits<long long>::max()));
-    builder->append("queryExecStats",
-                    BSON("collectionScans" << BSON(
-                             "total" << static_cast<long long>(collectionScanStats.collectionScans)
-                                     << "nonTailable"
-                                     << static_cast<long long>(
-                                            collectionScanStats.collectionScansNonTailable))));
-
-    return Status::OK();
-}
-
 BSONObj MongoInterfaceStandalone::getCollectionOptions(const NamespaceString& nss) {
     const auto infos = _client.getCollectionInfos(nss.db().toString(), BSON("name" << nss.coll()));
     if (infos.empty()) {
diff --git a/src/mongo/db/pipeline/process_interface_standalone.h b/src/mongo/db/pipeline/process_interface_standalone.h
index 8d7cf4693c4..1569e090c89 100644
--- a/src/mongo/db/pipeline/process_interface_standalone.h
+++ b/src/mongo/db/pipeline/process_interface_standalone.h
@@ -88,9 +88,6 @@ public:
     Status appendRecordCount(OperationContext* opCtx,
                              const NamespaceString& nss,
                              BSONObjBuilder* builder) const final;
-    Status appendQueryExecStats(OperationContext* opCtx,
-                                const NamespaceString& nss,
-                                BSONObjBuilder* builder) const final override;
     BSONObj getCollectionOptions(const NamespaceString& nss) final;
     void renameIfOptionsAndIndexesHaveNotChanged(OperationContext* opCtx,
                                                  const BSONObj& renameCommandObj,
diff --git a/src/mongo/db/pipeline/stub_mongo_process_interface.h b/src/mongo/db/pipeline/stub_mongo_process_interface.h
index 82950fdc427..a8a4a02e1e4 100644
--- a/src/mongo/db/pipeline/stub_mongo_process_interface.h
+++ b/src/mongo/db/pipeline/stub_mongo_process_interface.h
@@ -106,12 +106,6 @@ public:
         MONGO_UNREACHABLE;
     }
 
-    Status appendQueryExecStats(OperationContext* opCtx,
-                                const NamespaceString& nss,
-                                BSONObjBuilder* builder) const override {
-        MONGO_UNREACHABLE;
-    }
-
     BSONObj getCollectionOptions(const NamespaceString& nss) override {
         MONGO_UNREACHABLE;
     }
diff --git a/src/mongo/db/query/explain.cpp b/src/mongo/db/query/explain.cpp
index eb109928be4..709d8ffda4a 100644
--- a/src/mongo/db/query/explain.cpp
+++ b/src/mongo/db/query/explain.cpp
@@ -34,7 +34,6 @@
 #include "mongo/base/owned_pointer_vector.h"
 #include "mongo/bson/util/builder.h"
 #include "mongo/db/exec/cached_plan.h"
-#include "mongo/db/exec/collection_scan.h"
 #include "mongo/db/exec/count_scan.h"
 #include "mongo/db/exec/distinct_scan.h"
 #include "mongo/db/exec/idhack.h"
@@ -1016,13 +1015,6 @@ void Explain::getSummaryStats(const PlanExecutor& exec, PlanSummaryStats* statsO
             statsOut->replanned = cachedStats->replanned;
         } else if (STAGE_MULTI_PLAN == stages[i]->stageType()) {
             statsOut->fromMultiPlanner = true;
-        } else if (STAGE_COLLSCAN == stages[i]->stageType()) {
-            statsOut->collectionScans++;
-            const auto collScan = static_cast<const CollectionScan*>(stages[i]);
-            const auto collScanStats =
-                static_cast<const CollectionScanStats*>(collScan->getSpecificStats());
-            if (!collScanStats->tailable)
-                statsOut->collectionScansNonTailable++;
         }
     }
 }
diff --git a/src/mongo/db/query/find.cpp b/src/mongo/db/query/find.cpp
index f9de0152b5c..8f4132b1eaf 100644
--- a/src/mongo/db/query/find.cpp
+++ b/src/mongo/db/query/find.cpp
@@ -150,7 +150,7 @@ void endQueryOp(OperationContext* opCtx,
     curOp->debug().setPlanSummaryMetrics(summaryStats);
 
     if (collection) {
-        collection->infoCache()->notifyOfQuery(opCtx, summaryStats);
+        collection->infoCache()->notifyOfQuery(opCtx, summaryStats.indexesUsed);
     }
 
     if (curOp->shouldDBProfile()) {
diff --git a/src/mongo/db/query/plan_summary_stats.h b/src/mongo/db/query/plan_summary_stats.h
index a0ded1f2755..35deb4d83c0 100644
--- a/src/mongo/db/query/plan_summary_stats.h
+++ b/src/mongo/db/query/plan_summary_stats.h
@@ -50,14 +50,6 @@ struct PlanSummaryStats {
     // The number of milliseconds spent inside the root stage's work() method.
     long long executionTimeMillis = 0;
 
-    // The number of collection scans that occur during execution. Note that more than one
-    // collection scan may happen during execution (e.g. for $lookup execution).
-    long long collectionScans = 0;
-
-    // The number of collection scans that occur during execution which are nontailable. Note that
-    // more than one collection scan may happen during execution (e.g. for $lookup execution).
-    long long collectionScansNonTailable = 0;
-
     // Did this plan use an in-memory sort stage?
     bool hasSortStage = false;