如何在线程之间传递大型容器？

如何在线程之间传递大型容器？你能传递一个指针吗？陷阱，提示？我在下面举一个例子。

class Data {
    QMap<int, SomeClass> _m;  // большие
    std::array<SomeClass, 1024*1024> _a;
public:
    void initData();
};

class Worker : public QObject {
    Q_OBJECT
    Data *_d;
public:
    Worker() : QObject() { _d = new Data; }
signals:
    void finished(Data *d);
public slots:
    void process() { _d->initData(); emit finished(_d); }
};

class Controller : public QObject {
    Q_OBJECT
    Data *_d;
public:
    Controller(QObject *parent = nullptr) : QObject(parent) { }
    void start() {
        QThread *thr = new QThread;
        Worker *w = new Worker;
        w->moveToThread(thr);
        connect(thr, &QThread::started, w, &Worker::process);
        connect(w, &Worker::finished, this, [this] (Data *d) { _d = d;});
        connect(w, &Worker::finished, this, &Controller::finished);
        connect(w, &Worker::finished, thr, &QThread::quit);
        connect(w, &Worker::finished, w, &Worker::deleteLater);
        connect(thr, &QThread::finished, thr, &QThread::deleteLater);
        thr->start();
    }
signals:
    void finished(Data *d);
};

UDP：使用智能指针时出现问题：信号到插槽智能指针