diff --git a/thread/ThreadPool.cc b/thread/ThreadPool.cc
index dcaa19f..4e663a3 100644
--- a/thread/ThreadPool.cc
+++ b/thread/ThreadPool.cc
@@ -47,11 +47,17 @@ void ThreadPool::start(int numThreads)
 
 void ThreadPool::stop()
 {
-  running_ = false;
+  printf("starting to stop the pool.\n");
+  {
+    MutexLockGuard lock(mutex_);
+    running_ = false;
+  }
   cond_.notifyAll();
   for_each(threads_.begin(),
            threads_.end(),
            boost::bind(&muduo::Thread::join, _1));
+  threads_.clear();
+  printf("stop the pool successfully.\n");
 }
 
 void ThreadPool::run(const Task& task)
@@ -59,13 +65,13 @@ void ThreadPool::run(const Task& task)
   if (threads_.empty())
   {
     task();
+    return;
   }
-  else
   {
     MutexLockGuard lock(mutex_);
     queue_.push_back(task);
-    cond_.notify();
   }
+  cond_.notify();
 }
 
 ThreadPool::Task ThreadPool::take()
@@ -117,3 +123,33 @@ void ThreadPool::runInThread()
   }
 }
 
+
+
+// // bind cores
+// const int targetCore = bindcores_[i];
+// cpu_set_t cpuset;
+// CPU_ZERO(&cpuset);
+// CPU_SET(targetCore, &cpuset);
+// int ret = pthread_setaffinity_np(thread_[i], sizeof(cpu_set_t), &cpuset); // or std::thread::native_handle()
+//                                                                           // or pthread_self()
+// if (ret != 0)
+// {
+//     printf("[ThreadPool] thread %zu bind core %d  failed\n", i, targetCore);
+// }
+// else
+// {
+//     printf("[ThreadPool] thread %zu bind core %d  success\n", i, targetCore);
+// }
+
+// // 线程优先级
+// sched_param sp;
+// sp.sched_priority = sched_get_priority_max(SCHED_FIFO);
+// ret = pthread_setschedparam(thread_[i], SCHED_FIFO, &sp);
+// if (ret != 0)
+// {
+//     printf("[ThreadPool] thread %zu set  priority %d  failed\n", i, sp.sched_priority);
+// }
+// else
+// {
+//     printf("[ThreadPool] thread %zu set  priority %d  success\n", i, sp.sched_priority);
+// }
diff --git a/thread/ThreadPool.h b/thread/ThreadPool.h
index 042caa4..c322f19 100644
--- a/thread/ThreadPool.h
+++ b/thread/ThreadPool.h
@@ -17,6 +17,7 @@
 #include <boost/ptr_container/ptr_vector.hpp>
 
 #include <deque>
+#include <future>
 
 namespace muduo
 {
@@ -34,6 +35,26 @@ class ThreadPool : boost::noncopyable
 
   void run(const Task& f);
 
+  template<typename Func, typename... Args>
+  inline auto run_future(Func&& func, Args&&... args) -> std::future<typename std::result_of<Func(Args...)>::type>
+  {
+    if (threads_.empty()) {
+      func(args...);
+    }
+    using ret_type = typename std::result_of<Func(Args...)>::type;
+    auto task = std::make_shared<std::packaged_task<ret_type()>>(std::bind(std::forward<Func>(func), std::forward<Args>(args)...));
+    auto ret = task->get_future();
+    do {
+      MutexLockGuard lock(mutex_);
+      if (!running_) {
+        throw std::runtime_error("enqueue on stopped ThreadPool");
+      }
+      queue_.push_back([task]() { (*task)(); });
+    } while (0);
+    cond_.notify();
+    return std::move(ret);
+  }
+
  private:
   void runInThread();
   Task take();
diff --git a/thread/test/Factory_cpp20.cc b/thread/test/Factory_cpp20.cc
new file mode 100644
index 0000000..19e3ae8
--- /dev/null
+++ b/thread/test/Factory_cpp20.cc
@@ -0,0 +1,276 @@
+#include <map>
+
+#include "../Mutex.h"
+
+#include <assert.h>
+#include <stdio.h>
+
+#include <functional>
+
+using std::string;
+
+class Stock : boost::noncopyable
+{
+ public:
+  Stock(const string& name)
+    : name_(name)
+  {
+    printf(" Stock[%p] %s\n", this, name_.c_str());
+  }
+
+  ~Stock()
+  {
+    printf("~Stock[%p] %s\n", this, name_.c_str());
+  }
+
+  const string& key() const { return name_; }
+
+ private:
+  string name_;
+};
+
+namespace version1
+{
+
+// questionable code
+class StockFactory : boost::noncopyable
+{
+ public:
+
+  std::shared_ptr<Stock> get(const string& key)
+  {
+    muduo::MutexLockGuard lock(mutex_);
+    std::shared_ptr<Stock>& pStock = stocks_[key];
+    if (!pStock)
+    {
+      pStock.reset(new Stock(key));
+    }
+    return pStock;
+  }
+
+
+ private:
+  mutable muduo::MutexLock mutex_;
+  std::map<string, std::shared_ptr<Stock> > stocks_;
+};
+
+}
+
+namespace version2
+{
+
+class StockFactory : boost::noncopyable
+{
+ public:
+  std::shared_ptr<Stock> get(const string& key)
+  {
+    std::shared_ptr<Stock> pStock;
+    muduo::MutexLockGuard lock(mutex_);
+    std::weak_ptr<Stock>& wkStock = stocks_[key];
+    pStock = wkStock.lock();
+    if (!pStock)
+    {
+      pStock.reset(new Stock(key));
+      wkStock = pStock;
+    }
+    return pStock;
+  }
+
+ private:
+  mutable muduo::MutexLock mutex_;
+  std::map<string, std::weak_ptr<Stock> > stocks_;
+};
+
+}
+
+namespace version3
+{
+
+class StockFactory : boost::noncopyable
+{
+ public:
+
+  std::shared_ptr<Stock> get(const string& key)
+  {
+    std::shared_ptr<Stock> pStock;
+    muduo::MutexLockGuard lock(mutex_);
+    std::weak_ptr<Stock>& wkStock = stocks_[key];
+    pStock = wkStock.lock();
+    if (!pStock)
+    {
+      pStock.reset(new Stock(key), std::bind_front(&StockFactory::deleteStock, this));
+      wkStock = pStock;
+    }
+    return pStock;
+  }
+
+ private:
+
+  void deleteStock(Stock* stock)
+  {
+    printf("deleteStock[%p]\n", stock);
+    if (stock)
+    {
+      muduo::MutexLockGuard lock(mutex_);
+      stocks_.erase(stock->key());  // This is wrong, see removeStock below for correct implementation.
+    }
+    delete stock;  // sorry, I lied
+  }
+  mutable muduo::MutexLock mutex_;
+  std::map<string, std::weak_ptr<Stock> > stocks_;
+};
+
+}
+
+namespace version4
+{
+
+class StockFactory : public std::enable_shared_from_this<StockFactory>,
+                     boost::noncopyable
+{
+ public:
+
+  std::shared_ptr<Stock> get(const string& key)
+  {
+    std::shared_ptr<Stock> pStock;
+    muduo::MutexLockGuard lock(mutex_);
+    std::weak_ptr<Stock>& wkStock = stocks_[key];
+    pStock = wkStock.lock();
+    if (!pStock)
+    {
+      pStock.reset(new Stock(key),
+                   std::bind_front(&StockFactory::deleteStock, shared_from_this()));
+      wkStock = pStock;
+    }
+    return pStock;
+  }
+
+ private:
+
+  void deleteStock(Stock* stock)
+  {
+    printf("deleteStock[%p]\n", stock);
+    if (stock)
+    {
+      muduo::MutexLockGuard lock(mutex_);
+      stocks_.erase(stock->key());  // This is wrong, see removeStock below for correct implementation.
+    }
+    delete stock;  // sorry, I lied
+  }
+  mutable muduo::MutexLock mutex_;
+  std::map<string, std::weak_ptr<Stock> > stocks_;
+};
+
+}
+
+class StockFactory : public std::enable_shared_from_this<StockFactory>,
+                     boost::noncopyable
+{
+ public:
+  std::shared_ptr<Stock> get(const string& key)
+  {
+    std::shared_ptr<Stock> pStock;
+    muduo::MutexLockGuard lock(mutex_);
+    std::weak_ptr<Stock>& wkStock = stocks_[key];
+    pStock = wkStock.lock();
+    if (!pStock)
+    {
+      pStock.reset(new Stock(key),
+                   std::bind_front(&StockFactory::weakDeleteCallback,
+                            std::weak_ptr<StockFactory>(shared_from_this())));
+      wkStock = pStock;
+    }
+    return pStock;
+  }
+
+ private:
+  static void weakDeleteCallback(const std::weak_ptr<StockFactory>& wkFactory,
+                                 Stock* stock)
+  {
+    printf("weakDeleteStock[%p]\n", stock);
+    std::shared_ptr<StockFactory> factory(wkFactory.lock());
+    if (factory)
+    {
+      factory->removeStock(stock);
+    }
+    else
+    {
+      printf("factory died.\n");
+    }
+    delete stock;  // sorry, I lied
+  }
+
+  void removeStock(Stock* stock)
+  {
+    if (stock)
+    {
+      muduo::MutexLockGuard lock(mutex_);
+      auto it = stocks_.find(stock->key());
+      if (it != stocks_.end() && it->second.expired())
+      {
+        stocks_.erase(stock->key());
+      }
+    }
+  }
+
+ private:
+  mutable muduo::MutexLock mutex_;
+  std::map<string, std::weak_ptr<Stock> > stocks_;
+};
+
+void testLongLifeFactory()
+{
+  std::shared_ptr<StockFactory> factory(new StockFactory);
+  {
+    std::shared_ptr<Stock> stock = factory->get("NYSE:IBM");
+    std::shared_ptr<Stock> stock2 = factory->get("NYSE:IBM");
+    assert(stock == stock2);
+    // stock destructs here
+  }
+  // factory destructs here
+}
+
+void testShortLifeFactory()
+{
+  std::shared_ptr<Stock> stock;
+  {
+    std::shared_ptr<StockFactory> factory(new StockFactory);
+    stock = factory->get("NYSE:IBM");
+    std::shared_ptr<Stock> stock2 = factory->get("NYSE:IBM");
+    assert(stock == stock2);
+    // factory destructs here
+  }
+  // stock destructs here
+}
+
+int main()
+{
+  version1::StockFactory sf1;
+  version2::StockFactory sf2;
+  version3::StockFactory sf3;
+  std::shared_ptr<version3::StockFactory> sf4(new version3::StockFactory);
+  std::shared_ptr<StockFactory> sf5(new StockFactory);
+
+  {
+  std::shared_ptr<Stock> s1 = sf1.get("stock1");
+  }
+
+  {
+  std::shared_ptr<Stock> s2 = sf2.get("stock2");
+  }
+
+  {
+  std::shared_ptr<Stock> s3 = sf3.get("stock3");
+  }
+
+  {
+  std::shared_ptr<Stock> s4 = sf4->get("stock4");
+  }
+
+  {
+  std::shared_ptr<Stock> s5 = sf5->get("stock5");
+  }
+
+  testLongLifeFactory();
+  testShortLifeFactory();
+}
diff --git a/thread/test/ThreadPool_test.cc b/thread/test/ThreadPool_test.cc
index f8ba48c..a253b93 100644
--- a/thread/test/ThreadPool_test.cc
+++ b/thread/test/ThreadPool_test.cc
@@ -17,8 +17,9 @@ void printString(const std::string& str)
 int main()
 {
   muduo::ThreadPool pool("MainThreadPool");
-  pool.start(5);
 
+
+  pool.start(5);
   pool.run(print);
   pool.run(print);
   for (int i = 0; i < 100; ++i)
@@ -32,5 +33,22 @@ int main()
   pool.run(boost::bind(&muduo::CountDownLatch::countDown, &latch));
   latch.wait();
   pool.stop();
+
+  printf("Testing run_future\n");
+  pool.start(5);
+  pool.run(print);
+  pool.run(print);
+  std::vector<std::future<void>> futures;
+  for (int i = 0; i < 100; ++i)
+  {
+    char buf[32];
+    snprintf(buf, sizeof buf, "task %d", i);
+    futures.emplace_back(std::move(pool.run_future(boost::bind(printString, std::string(buf))))); 
+  }
+  for (auto& future : futures)
+  {
+    future.get();
+  }
+  pool.stop();
 }