SERVER-34199 Remove serverStatus timing section from FTDC

(cherry picked from commit a222ef5e647ac527f7d4f8636bcacd6cc0ae6b8e)

2 files changed, 19 insertions, 2 deletions

diff --git a/src/mongo/db/commands/server_status.cpp b/src/mongo/db/commands/server_status.cpp
index 89eae376373..01fd9569fc4 100644
--- a/src/mongo/db/commands/server_status.cpp
+++ b/src/mongo/db/commands/server_status.cpp
@@ -50,6 +50,10 @@ using std::map;
 using std::string;
 using std::stringstream;
 
+namespace {
+constexpr auto kTimingSection = "timing"_sd;
+}  // namespace
+
 class CmdServerStatus : public BasicCommand {
 public:
     CmdServerStatus() : BasicCommand("serverStatus"), _started(Date_t::now()), _runCalled(false) {}
@@ -154,13 +158,24 @@ public:
         if (runElapsed > Milliseconds(1000)) {
             BSONObj t = timeBuilder.obj();
             log() << "serverStatus was very slow: " << t;
-            result.append("timing", t);
+
+            bool include_timing = true;
+            const auto& elem = cmdObj[kTimingSection];
+            if (!elem.eoo()) {
+                include_timing = elem.trueValue();
+            }
+
+            if (include_timing) {
+                result.append(kTimingSection, t);
+            }
         }
 
         return true;
     }
 
     void addSection(ServerStatusSection* section) {
+        // Disallow adding a section named "timing" as it is reserved for the server status command.
+        dassert(section->getSectionName() != kTimingSection);
         verify(!_runCalled);
         _sections[section->getSectionName()] = section;
     }
diff --git a/src/mongo/db/ftdc/ftdc_server.cpp b/src/mongo/db/ftdc/ftdc_server.cpp
index 95eb2b21b83..a46a0106262 100644
--- a/src/mongo/db/ftdc/ftdc_server.cpp
+++ b/src/mongo/db/ftdc/ftdc_server.cpp
@@ -293,12 +293,14 @@ void startFTDC(boost::filesystem::path& path,
     // migration status. This section triggers too many schema changes in the serverStatus which
     // hurt ftdc compression efficiency, because its output varies depending on the list of active
     // migrations.
+    // "timing" is filtered out because it triggers frequent schema changes.
     // TODO: do we need to enable "sharding" on MongoS?
     controller->addPeriodicCollector(stdx::make_unique<FTDCSimpleInternalCommandCollector>(
         "serverStatus",
         "serverStatus",
         "",
-        BSON("serverStatus" << 1 << "tcMalloc" << true << "sharding" << false)));
+        BSON("serverStatus" << 1 << "tcMalloc" << true << "sharding" << false << "timing"
+                            << false)));
 
     registerCollectors(controller.get());