message: Reserve threads vector
  Summary: Avoid repeated overhead when inserting threads.
diff: @@ -257,7 +257,6 @@ void SpartaWorkQueue<Input, Executor>::add_item(Input task, size_t worker_id) {
  */
  template <class Input, typename Executor>
  void SpartaWorkQueue<Input, Executor>::run_all() {
  - std::vector<boost::thread> all_threads;
  m_state_counters.num_non_empty = 0;
  m_state_counters.num_running = 0;
  m_state_counters.waiter->take_all();
  @@ -304,6 +303,9 @@ void SpartaWorkQueue<Input, Executor>::run_all() {
  ++m_state_counters.num_non_empty;
  }
  }
  +
  + std::vector<boost::thread> all_threads;
  + all_threads.reserve(m_num_threads);
  for (size_t i = 0; i < m_num_threads; ++i) {
  boost::thread::attributes attrs;
  attrs.set_stack_size(8 * 1024 * 1024);
  