sequence-benchmark.cc

template <class Sync>
void Sequence(benchmark::State& state) {
  static Sync sync;
  static std::atomic<uint64> pseq{0};
  static uint64 cseq{0};
  std::priority_queue<int, std::vector<int>, std::greater<int>> queue;
  typename Sync::Mem mem;
  for (auto _ : state) {
    uint64 p = pseq.fetch_add(std::memory_order_relaxed);
    sync.Run(&mem, [&, p] {
      queue.push(p);
      uint64 c = cseq;
      while (!queue.empty() && c == queue.top()) {
        ++c;
        queue.pop();
      }
      cseq = c;
    });
  }
}

// Benchmark                                    Time(ns)        CPU(ns)     Iterations
// -----------------------------------------------------------------------------------
// Sequence<ActionChainNoPooling>/threads:1           61.8           61.8      9789886  
// Sequence<ActionChainNoPooling>/threads:4           95.9          308        2092948  
// Sequence<ActionChainNoPooling>/threads:12          73.9          499        1200000  
// Sequence<ActionChainNoPooling>/threads:16          69.5          488        1423632  
// Sequence<ActionChainNoPooling>/threads:128         64.7          444        1280000  
// Sequence<ActionChain>/threads:1                    38.4           38.4     16257661  
// Sequence<ActionChain>/threads:4                    79.4          250        2352984  
// Sequence<ActionChain>/threads:12                   64.6          455        1200000  
// Sequence<ActionChain>/threads:16                   63.3          434        1600000  
// Sequence<ActionChain>/threads:128                  67.3          470        1280000  
// Sequence<CriticalSection>/threads:1                29.5           29.5     22470611  
// Sequence<CriticalSection>/threads:4               157            600         949304  
// Sequence<CriticalSection>/threads:12              214           1656         409992  
// Sequence<CriticalSection>/threads:16              195           1463         457056  
// Sequence<CriticalSection>/threads:128             188           1289         540032  
// Sequence<Unsynchronized>                           23.0           23.3     33835886