Class ThreadPoolBuilder

be/src/kudu/util/threadpool.h:113–146

ThreadPool takes a lot of arguments. We provide sane defaults with a builder. name: Used for debugging output and default names of the worker threads. Since thread names are limited to 16 characters on Linux, it's good to choose a short name here. Required. trace_metric_prefix: used to prefix the names of TraceMetric counters. When a task on a thread pool has an associated trace, the thread pool

//    Default: not set.
//
class ThreadPoolBuilder {
 public:
  explicit ThreadPoolBuilder(std::string name);

  // Note: We violate the style guide by returning mutable references here
  // in order to provide traditional Builder pattern conveniences.
  ThreadPoolBuilder& set_trace_metric_prefix(const std::string& prefix);
  ThreadPoolBuilder& set_min_threads(int min_threads);
  ThreadPoolBuilder& set_max_threads(int max_threads);
  ThreadPoolBuilder& set_max_queue_size(int max_queue_size);
  ThreadPoolBuilder& set_idle_timeout(const MonoDelta& idle_timeout);
  ThreadPoolBuilder& set_queue_overload_threshold(const MonoDelta& threshold);
  ThreadPoolBuilder& set_metrics(ThreadPoolMetrics metrics);
  ThreadPoolBuilder& set_enable_scheduler();
  ThreadPoolBuilder& set_schedule_period_ms(uint32_t schedule_period_ms);

  // Instantiate a new ThreadPool with the existing builder arguments.
  Status Build(std::unique_ptr<ThreadPool>* pool) const;

 private:
  friend class ThreadPool;
  const std::string name_;
  std::string trace_metric_prefix_;
  int min_threads_;
  int max_threads_;
  int max_queue_size_;
  MonoDelta idle_timeout_;
  MonoDelta queue_overload_threshold_;
  ThreadPoolMetrics metrics_;
  bool enable_scheduler_;
  uint32_t schedule_period_ms_ = 100;

  DISALLOW_COPY_AND_ASSIGN(ThreadPoolBuilder);
};

// SchedulerThread for asynchronized delay task execution.
//