    void start() override {
      tls_->set([](Event::Dispatcher& dispatcher) -> ThreadLocal::ThreadLocalObjectSharedPtr {
        return std::make_shared<NullThreadLocalOverloadState>(dispatcher);
      });
    }
    void start() override {
      tls_->set([](Event::Dispatcher& dispatcher) -> ThreadLocal::ThreadLocalObjectSharedPtr {
        return std::make_shared<NullThreadLocalOverloadState>(dispatcher);
      });
    }