SERVER-36099 Trim FTDC connection pool stats

4 files changed, 34 insertions, 20 deletions

diff --git a/src/mongo/client/replica_set_monitor.cpp b/src/mongo/client/replica_set_monitor.cpp
index 21b2e42b4ad..25927212728 100644
--- a/src/mongo/client/replica_set_monitor.cpp
+++ b/src/mongo/client/replica_set_monitor.cpp
@@ -157,6 +157,15 @@ struct HostNotIn {
     const std::set<HostAndPort>& _hosts;
 };
 
+int32_t pingTimeMillis(const Node& node) {
+    auto latencyMillis = node.latencyMicros / 1000;
+    if (latencyMillis > numeric_limits<int32_t>::max()) {
+        // In particular, Node::unknownLatency does not fit in an int32.
+        return numeric_limits<int32_t>::max();
+    }
+    return latencyMillis;
+}
+
 /**
  * Replica set refresh period on the task executor.
  */
@@ -397,12 +406,21 @@ ReplicaSetChangeNotifier& ReplicaSetMonitor::getNotifier() {
 }
 
 // TODO move to correct order with non-statics before pushing
-void ReplicaSetMonitor::appendInfo(BSONObjBuilder& bsonObjBuilder) const {
+void ReplicaSetMonitor::appendInfo(BSONObjBuilder& bsonObjBuilder, bool forFTDC) const {
     stdx::lock_guard<stdx::mutex> lk(_state->mutex);
 
+    BSONObjBuilder monitorInfo(bsonObjBuilder.subobjStart(getName()));
+    if (forFTDC) {
+        for (size_t i = 0; i < _state->nodes.size(); i++) {
+            const Node& node = _state->nodes[i];
+            monitorInfo.appendNumber(node.host.toString(), pingTimeMillis(node));
+        }
+        return;
+    }
+
     // NOTE: the format here must be consistent for backwards compatibility
-    BSONArrayBuilder hosts(bsonObjBuilder.subarrayStart("hosts"));
-    for (unsigned i = 0; i < _state->nodes.size(); i++) {
+    BSONArrayBuilder hosts(monitorInfo.subarrayStart("hosts"));
+    for (size_t i = 0; i < _state->nodes.size(); i++) {
         const Node& node = _state->nodes[i];
 
         BSONObjBuilder builder;
@@ -411,15 +429,7 @@ void ReplicaSetMonitor::appendInfo(BSONObjBuilder& bsonObjBuilder) const {
         builder.append("ismaster", node.isMaster);  // intentionally not camelCase
         builder.append("hidden", false);            // we don't keep hidden nodes in the set
         builder.append("secondary", node.isUp && !node.isMaster);
-
-        int32_t pingTimeMillis = 0;
-        if (node.latencyMicros / 1000 > numeric_limits<int32_t>::max()) {
-            // In particular, Node::unknownLatency does not fit in an int32.
-            pingTimeMillis = numeric_limits<int32_t>::max();
-        } else {
-            pingTimeMillis = node.latencyMicros / 1000;
-        }
-        builder.append("pingTimeMillis", pingTimeMillis);
+        builder.append("pingTimeMillis", pingTimeMillis(node));
 
         if (!node.tags.isEmpty()) {
             builder.append("tags", node.tags);
@@ -427,7 +437,6 @@ void ReplicaSetMonitor::appendInfo(BSONObjBuilder& bsonObjBuilder) const {
 
         hosts.append(builder.obj());
     }
-    hosts.done();
 }
 
 void ReplicaSetMonitor::shutdown() {
diff --git a/src/mongo/client/replica_set_monitor.h b/src/mongo/client/replica_set_monitor.h
index a306b1b9547..b28364c6a25 100644
--- a/src/mongo/client/replica_set_monitor.h
+++ b/src/mongo/client/replica_set_monitor.h
@@ -155,9 +155,10 @@ public:
     bool contains(const HostAndPort& server) const;
 
     /**
-     * Writes information about our cached view of the set to a BSONObjBuilder.
+     * Writes information about our cached view of the set to a BSONObjBuilder. If
+     * forFTDC, trim to minimize its size for full-time diagnostic data capture.
      */
-    void appendInfo(BSONObjBuilder& b) const;
+    void appendInfo(BSONObjBuilder& b, bool forFTDC = false) const;
 
     /**
      * Returns true if the monitor knows a usable primary from it's interal view.
diff --git a/src/mongo/client/replica_set_monitor_manager.cpp b/src/mongo/client/replica_set_monitor_manager.cpp
index f8f6078b23a..dff3d8a16c4 100644
--- a/src/mongo/client/replica_set_monitor_manager.cpp
+++ b/src/mongo/client/replica_set_monitor_manager.cpp
@@ -203,19 +203,22 @@ void ReplicaSetMonitorManager::removeAllMonitors() {
     }
 }
 
-void ReplicaSetMonitorManager::report(BSONObjBuilder* builder) {
+void ReplicaSetMonitorManager::report(BSONObjBuilder* builder, bool forFTDC) {
     // Don't hold _mutex the whole time to avoid ever taking a monitor's mutex while holding the
     // manager's mutex.  Otherwise we could get a deadlock between the manager's, monitor's, and
     // ShardRegistry's mutex due to the ReplicaSetMonitor's AsynchronousConfigChangeHook potentially
     // calling ShardRegistry::updateConfigServerConnectionString.
     auto setNames = getAllSetNames();
+
+    BSONObjBuilder setStats(
+        builder->subobjStart(forFTDC ? "replicaSetPingTimesMillis" : "replicaSets"));
+
     for (const auto& setName : setNames) {
         auto monitor = getMonitor(setName);
         if (!monitor) {
             continue;
         }
-        BSONObjBuilder monitorInfo(builder->subobjStart(setName));
-        monitor->appendInfo(monitorInfo);
+        monitor->appendInfo(setStats, forFTDC);
     }
 }
 
diff --git a/src/mongo/client/replica_set_monitor_manager.h b/src/mongo/client/replica_set_monitor_manager.h
index 1adf42fb16d..b0a08f8f4e5 100644
--- a/src/mongo/client/replica_set_monitor_manager.h
+++ b/src/mongo/client/replica_set_monitor_manager.h
@@ -86,9 +86,10 @@ public:
     void shutdown();
 
     /**
-     * Reports information about the replica sets tracked by us, for diagnostic purposes.
+     * Reports information about the replica sets tracked by us, for diagnostic purposes. If
+     * forFTDC, trim to minimize its size for full-time diagnostic data capture.
      */
-    void report(BSONObjBuilder* builder);
+    void report(BSONObjBuilder* builder, bool forFTDC = false);
 
     /**
      * Returns an executor for running RSM tasks.