add some basic send tracking

assignment-client/src/entities/EntityServer.cpp

@@ -266,3 +266,49 @@ void EntityServer::readAdditionalConfiguration(const QJsonObject& settingsSectio
     tree->setWantEditLogging(wantEditLogging);
     tree->setWantTerseEditLogging(wantTerseEditLogging);
 }
+
+void EntityServer::trackSend(const QUuid& dataID, const QUuid& viewerNode) {
+    QWriteLocker locker(&_viewerSendingStatsLock);
+    _viewerSendingStats[viewerNode] = usecTimestampNow();
+}
+
+
+QString EntityServer::serverSubclassStats() {
+    QLocale locale(QLocale::English);
+    QString statsString;
+
+    // display memory usage stats
+    statsString += "<b>Entity Server Memory Statistics</b>\r\n";
+    statsString += QString().sprintf("EntityTreeElement size... %ld bytes\r\n", sizeof(EntityTreeElement));
+    statsString += QString().sprintf("       EntityItem size... %ld bytes\r\n", sizeof(EntityItem));
+    statsString += "\r\n\r\n";
+
+    statsString += "<b>Entity Server Sending to Viewer Statistics</b>\r\n";
+    statsString += "----- Viewer Node ID -----------------    ---------- Last Sent To ----------\r\n";
+
+    int viewers = 0;
+    const int COLUMN_WIDTH = 24;
+
+    {
+        QReadLocker locker(&_viewerSendingStatsLock);
+        quint64 now = usecTimestampNow();
+
+        for (auto key : _viewerSendingStats.keys()) {
+            quint64 lastSentAt = _viewerSendingStats[key];
+            quint64 elapsed = now - lastSentAt;
+            double msecsAgo = (double)(elapsed / USECS_PER_MSEC);
+            statsString += key.toString();
+            statsString += "    ";
+            statsString += QString("%1 msecs ago\r\n")
+                .arg(locale.toString((double)msecsAgo).rightJustified(COLUMN_WIDTH, ' '));
+
+            viewers++;
+        }
+    }
+    if (viewers < 1) {
+        statsString += "    no viewers... \r\n";
+    }
+    statsString += "\r\n\r\n";
+
+    return statsString;
+}

assignment-client/src/entities/EntityServer.h

@@ -44,6 +44,9 @@ public:
 
     virtual void entityCreated(const EntityItem& newEntity, const SharedNodePointer& senderNode) override;
     virtual void readAdditionalConfiguration(const QJsonObject& settingsSectionObject) override;
+    virtual QString serverSubclassStats();
+
+    virtual void trackSend(const QUuid& dataID, const QUuid& viewerNode);
 
 public slots:
     void pruneDeletedEntities();
@@ -57,6 +60,9 @@ private slots:
 private:
     EntitySimulation* _entitySimulation;
     QTimer* _pruneDeletedEntitiesTimer = nullptr;
+
+    QReadWriteLock _viewerSendingStatsLock;
+    QMap<QUuid,quint64> _viewerSendingStats;
 };
 
 #endif // hifi_EntityServer_h

assignment-client/src/octree/OctreeSendThread.cpp

@@ -467,6 +467,12 @@ int OctreeSendThread::packetDistributor(OctreeQueryNode* nodeData, bool viewFrus
                                                  isFullScene, &nodeData->stats, _myServer->getJurisdiction(),
                                                  &nodeData->extraEncodeData);
 
+                    // Our trackSend() function is implemented by the server subclass, and will be called back
+                    // during the encodeTreeBitstream() as new entities/data elements are sent 
+                    params.trackSend = [this](const QUuid& id) {
+                        _myServer->trackSend(id, _nodeUUID);
+                    };
+
                     // TODO: should this include the lock time or not? This stat is sent down to the client,
                     // it seems like it may be a good idea to include the lock time as part of the encode time
                     // are reported to client. Since you can encode without the lock

assignment-client/src/octree/OctreeServer.cpp

@@ -821,6 +821,11 @@ bool OctreeServer::handleHTTPRequest(HTTPConnection* connection, const QUrl& url
             .arg(locale.toString((uint)checkSum).rightJustified(16, ' '));
 
         statsString += "\r\n\r\n";
+
+        statsString += serverSubclassStats();
+
+        statsString += "\r\n\r\n";
+
         statsString += "</pre>\r\n";
         statsString += "</doc></html>";
 

assignment-client/src/octree/OctreeServer.h

@@ -79,6 +79,8 @@ public:
     virtual void beforeRun() { }
     virtual bool hasSpecialPacketsToSend(const SharedNodePointer& node) { return false; }
     virtual int sendSpecialPackets(const SharedNodePointer& node, OctreeQueryNode* queryNode, int& packetsSent) { return 0; }
+    virtual QString serverSubclassStats() { return QString(); }
+    virtual void trackSend(const QUuid& dataID, const QUuid& viewerNode) { }
 
     static float SKIP_TIME; // use this for trackXXXTime() calls for non-times
 

libraries/entities/src/EntityItem.cpp

@@ -311,6 +311,11 @@ OctreeElement::AppendState EntityItem::appendEntityData(OctreePacketData* packet
         entityTreeElementExtraEncodeData->entities.insert(getEntityItemID(), propertiesDidntFit);
     }
 
+    // if any part of our entity was sent, call trackSend
+    if (appendState != OctreeElement::NONE) {
+        params.trackSend(getID());
+    }
+
     return appendState;
 }
 

libraries/octree/src/Octree.h

@@ -176,6 +176,8 @@ public:
             case OCCLUDED: return QString("OCCLUDED"); break;
         }
     }
+
+    std::function<void(const QUuid&)> trackSend { [](const QUuid&){} };
 };
 
 class ReadElementBufferToTreeArgs {