Function ThreadPoolSubmit

cpp/src/arrow/util/thread_pool_benchmark.cc:123–152

Benchmark ThreadPool::Submit

// Benchmark ThreadPool::Submit
static void ThreadPoolSubmit(benchmark::State& state) {  // NOLINT non-const reference
  const auto nthreads = static_cast<int>(state.range(0));
  const auto workload_size = static_cast<int32_t>(state.range(1));

  Workload workload(workload_size);

  const int32_t nspawns = 10000000 / workload_size + 1;

  for (auto _ : state) {
    state.PauseTiming();
    auto pool = *ThreadPool::Make(nthreads);
    std::atomic<int32_t> n_finished{0};
    state.ResumeTiming();

    for (int32_t i = 0; i < nspawns; ++i) {
      // Pass the task by reference to avoid copying it around
      (void)DeferNotOk(pool->Submit(std::ref(workload))).Then([&]() {
        n_finished.fetch_add(1);
      });
    }

    // Wait for all tasks to finish
    ABORT_NOT_OK(pool->Shutdown(true /* wait */));
    ASSERT_EQ(n_finished.load(), nspawns);
    state.PauseTiming();
    pool.reset();
    state.ResumeTiming();
  }
  state.SetItemsProcessed(state.iterations() * nspawns);
}

// Benchmark serial TaskGroup
static void SerialTaskGroup(benchmark::State& state) {  // NOLINT non-const reference