diff -uprN boost_1_55_0.orig/boost/asio/detail/impl/task_io_service.ipp boost_1_55_0.patch/boost/asio/detail/impl/task_io_service.ipp
--- boost_1_55_0.orig/boost/asio/detail/impl/task_io_service.ipp	2013-05-20 16:32:20.000000000 +0400
+++ boost_1_55_0.patch/boost/asio/detail/impl/task_io_service.ipp	2015-03-06 21:52:06.000000000 +0400
@@ -77,13 +77,26 @@ struct task_io_service::work_cleanup
     {
       lock_->lock();
       task_io_service_->op_queue_.push(this_thread_->private_op_queue);
+      lock_->unlock();
     }
 #endif // defined(BOOST_ASIO_HAS_THREADS)
+
+    // If the last handler put a new work into the empty queue
+    // we should wake up a thread for it
+    if(check_new_handlers_)
+    {
+      lock_->lock();
+      if(!task_io_service_->op_queue_.empty())
+        task_io_service_->wake_one_thread_and_unlock(*lock_);
+      else
+        lock_->unlock();
+    }
   }
 
   task_io_service* task_io_service_;
   mutex::scoped_lock* lock_;
   thread_info* this_thread_;
+  bool check_new_handlers_;
 };
 
 task_io_service::task_io_service(
@@ -377,7 +390,7 @@ std::size_t task_io_service::do_run_one(
           lock.unlock();
 
         // Ensure the count of outstanding work is decremented on block exit.
-        work_cleanup on_exit = { this, &lock, &this_thread };
+        work_cleanup on_exit = { this, &lock, &this_thread, !more_handlers && !one_thread_ };
         (void)on_exit;
 
         // Complete the operation. May throw an exception. Deletes the object.
diff -uprN boost_1_55_0.orig/boost/asio/detail/posix_event.hpp boost_1_55_0.patch/boost/asio/detail/posix_event.hpp
--- boost_1_55_0.orig/boost/asio/detail/posix_event.hpp	2013-05-20 16:32:20.000000000 +0400
+++ boost_1_55_0.patch/boost/asio/detail/posix_event.hpp	2015-03-04 18:03:46.000000000 +0400
@@ -58,8 +58,8 @@ public:
   {
     BOOST_ASIO_ASSERT(lock.locked());
     signalled_ = true;
-    lock.unlock();
     ::pthread_cond_signal(&cond_); // Ignore EINVAL.
+    lock.unlock();
   }
 
   // Reset the event.