- std::map<Prio, tbb::concurrent_queue<T>, std::greater<Prio>> queues_by_priority_;
- semaphore space_available_;
- semaphore elements_available_;
- mutable boost::mutex capacity_mutex_;
- size_type capacity_;
+ std::map<Prio, tbb::concurrent_queue<T>, std::greater<Prio>> queues_by_priority_;
+ size_type capacity_;
+ semaphore space_available_ { capacity_ };
+ semaphore elements_available_ { 0u };
+ mutable boost::mutex capacity_mutex_;