std::shared_ptr<Butler> _butler;
std::list<Frame> _latency_history;
/** Mutex to protect _latency_history */
mutable boost::mutex _latency_history_mutex;
std::shared_ptr<Butler> _butler;
std::list<Frame> _latency_history;
/** Mutex to protect _latency_history */
mutable boost::mutex _latency_history_mutex;