SERVER-23257 Report keysExamined/docsExamined/hasSortStage where valid

4 files changed, 84 insertions, 40 deletions

diff --git a/src/mongo/db/query/explain.cpp b/src/mongo/db/query/explain.cpp
index 890d50e9021..a1eb04332e3 100644
--- a/src/mongo/db/query/explain.cpp
+++ b/src/mongo/db/query/explain.cpp
@@ -41,6 +41,7 @@
 #include "mongo/db/exec/text.h"
 #include "mongo/db/query/get_executor.h"
 #include "mongo/db/query/plan_executor.h"
+#include "mongo/db/query/plan_summary_stats.h"
 #include "mongo/db/query/query_planner.h"
 #include "mongo/db/query/query_settings.h"
 #include "mongo/db/query/stage_builder.h"
diff --git a/src/mongo/db/query/explain.h b/src/mongo/db/query/explain.h
index 21edf161597..95fc193cbb2 100644
--- a/src/mongo/db/query/explain.h
+++ b/src/mongo/db/query/explain.h
@@ -40,40 +40,7 @@ namespace mongo {
 
 class Collection;
 class OperationContext;
-
-/**
- * A container for the summary statistics that the profiler, slow query log, and
- * other non-explain debug mechanisms may want to collect.
- */
-struct PlanSummaryStats {
-    // The number of results returned by the plan.
-    size_t nReturned = 0U;
-
-    // The total number of index keys examined by the plan.
-    size_t totalKeysExamined = 0U;
-
-    // The total number of documents examined by the plan.
-    size_t totalDocsExamined = 0U;
-
-    // The number of milliseconds spent inside the root stage's work() method.
-    long long executionTimeMillis = 0;
-
-    // Did this plan use the fast path for key-value retrievals on the _id index?
-    bool isIdhack = false;
-
-    // Did this plan use an in-memory sort stage?
-    bool hasSortStage = false;
-
-    // The names of each index used by the plan.
-    std::set<std::string> indexesUsed;
-
-    // Was this plan a result of using the MultiPlanStage to select a winner among several
-    // candidates?
-    bool fromMultiPlanner = false;
-
-    // Was a replan triggered during the execution of this query?
-    bool replanned = false;
-};
+struct PlanSummaryStats;
 
 /**
  * Namespace for the collection of static methods used to generate explain information.
diff --git a/src/mongo/db/query/find.cpp b/src/mongo/db/query/find.cpp
index edc77d515bf..c54be93d0e5 100644
--- a/src/mongo/db/query/find.cpp
+++ b/src/mongo/db/query/find.cpp
@@ -49,6 +49,7 @@
 #include "mongo/db/query/find_common.h"
 #include "mongo/db/query/get_executor.h"
 #include "mongo/db/query/internal_plans.h"
+#include "mongo/db/query/plan_summary_stats.h"
 #include "mongo/db/query/query_planner_params.h"
 #include "mongo/db/repl/replication_coordinator_global.h"
 #include "mongo/db/s/collection_sharding_state.h"
@@ -153,12 +154,7 @@ void endQueryOp(OperationContext* txn,
     // Fill out curop based on explain summary statistics.
     PlanSummaryStats summaryStats;
     Explain::getSummaryStats(exec, &summaryStats);
-    curop->debug().hasSortStage = summaryStats.hasSortStage;
-    curop->debug().keysExamined = summaryStats.totalKeysExamined;
-    curop->debug().docsExamined = summaryStats.totalDocsExamined;
-    curop->debug().idhack = summaryStats.isIdhack;
-    curop->debug().fromMultiPlanner = summaryStats.fromMultiPlanner;
-    curop->debug().replanned = summaryStats.replanned;
+    curop->debug().setPlanSummaryMetrics(summaryStats);
 
     if (collection) {
         collection->infoCache()->notifyOfQuery(txn, summaryStats.indexesUsed);
@@ -393,6 +389,12 @@ QueryResult::View getMore(OperationContext* txn,
         exec->restoreState();
         PlanExecutor::ExecState state;
 
+        // We report keysExamined and docsExamined to OpDebug for a given getMore operation. To
+        // obtain these values we need to take a diff of the pre-execution and post-execution
+        // metrics, as they accumulate over the course of a cursor's lifetime.
+        PlanSummaryStats preExecutionStats;
+        Explain::getSummaryStats(*exec, &preExecutionStats);
+
         generateBatch(ntoreturn, cc, &bb, &numResults, &slaveReadTill, &state);
 
         // If this is an await data cursor, and we hit EOF without generating any results, then
@@ -420,6 +422,12 @@ QueryResult::View getMore(OperationContext* txn,
             generateBatch(ntoreturn, cc, &bb, &numResults, &slaveReadTill, &state);
         }
 
+        PlanSummaryStats postExecutionStats;
+        Explain::getSummaryStats(*exec, &postExecutionStats);
+        postExecutionStats.totalKeysExamined -= preExecutionStats.totalKeysExamined;
+        postExecutionStats.totalDocsExamined -= preExecutionStats.totalDocsExamined;
+        curop.debug().setPlanSummaryMetrics(postExecutionStats);
+
         // We have to do this before re-acquiring locks in the agg case because
         // shouldSaveCursorGetMore() can make a network call for agg cursors.
         //
diff --git a/src/mongo/db/query/plan_summary_stats.h b/src/mongo/db/query/plan_summary_stats.h
new file mode 100644
index 00000000000..8168ea9f401
--- /dev/null
+++ b/src/mongo/db/query/plan_summary_stats.h
@@ -0,0 +1,68 @@
+/*    Copyright 2016 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the GNU Affero General Public License in all respects
+ *    for all of the code used other than as permitted herein. If you modify
+ *    file(s) with this exception, you may extend this exception to your
+ *    version of the file(s), but you are not obligated to do so. If you do not
+ *    wish to do so, delete this exception statement from your version. If you
+ *    delete this exception statement from all source files in the program,
+ *    then also delete it in the license file.
+ */
+
+#pragma once
+
+#include <string>
+
+namespace mongo {
+
+/**
+ * A container for the summary statistics that the profiler, slow query log, and
+ * other non-explain debug mechanisms may want to collect.
+ */
+struct PlanSummaryStats {
+    // The number of results returned by the plan.
+    size_t nReturned = 0U;
+
+    // The total number of index keys examined by the plan.
+    size_t totalKeysExamined = 0U;
+
+    // The total number of documents examined by the plan.
+    size_t totalDocsExamined = 0U;
+
+    // The number of milliseconds spent inside the root stage's work() method.
+    long long executionTimeMillis = 0;
+
+    // Did this plan use the fast path for key-value retrievals on the _id index?
+    bool isIdhack = false;
+
+    // Did this plan use an in-memory sort stage?
+    bool hasSortStage = false;
+
+    // The names of each index used by the plan.
+    std::set<std::string> indexesUsed;
+
+    // Was this plan a result of using the MultiPlanStage to select a winner among several
+    // candidates?
+    bool fromMultiPlanner = false;
+
+    // Was a replan triggered during the execution of this query?
+    bool replanned = false;
+};
+
+}  // namespace mongo