Moved files [#METR-17973].

dbms/include/DB/DataStreams/AsynchronousBlockInputStream.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 
 #include <Poco/Event.h>
 

dbms/include/DB/IO/AsynchronousWriteBuffer.h

@@ -7,7 +7,7 @@
 #include <Poco/SharedPtr.h>
 #include <Poco/Net/NetException.h>
 
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 
 #include <DB/IO/WriteBuffer.h>
 

dbms/include/DB/Interpreters/Aggregator.h

@@ -5,7 +5,7 @@
 #include <functional>
 
 #include <common/logger_useful.h>
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 
 #include <DB/Core/StringRef.h>
 #include <DB/Common/Arena.h>

dbms/include/DB/Interpreters/Compiler.h

@@ -9,7 +9,7 @@
 #include <unordered_map>
 
 #include <common/logger_useful.h>
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 
 #include <DB/Core/Types.h>
 #include <DB/Core/Exception.h>

dbms/src/Client/Benchmark.cpp

@@ -12,7 +12,7 @@
 #include <Poco/Util/Application.h>
 
 #include <DB/Common/Stopwatch.h>
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 #include <stats/ReservoirSampler.h>
 
 #include <boost/program_options.hpp>

dbms/src/Common/tests/parallel_aggregation.cpp

@@ -16,7 +16,7 @@
 #include <DB/IO/CompressedReadBuffer.h>
 
 #include <DB/Common/Stopwatch.h>
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 
 
 typedef UInt64 Key;

dbms/src/Common/tests/parallel_aggregation2.cpp

@@ -16,7 +16,7 @@
 #include <DB/IO/CompressedReadBuffer.h>
 
 #include <DB/Common/Stopwatch.h>
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 
 
 typedef UInt64 Key;

dbms/src/DataStreams/tests/glue_streams.cpp

@@ -1,7 +1,7 @@
 #include <iostream>
 #include <iomanip>
 
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 
 #include <DB/IO/WriteBufferFromFileDescriptor.h>
 

dbms/src/Interpreters/loadMetadata.cpp

@@ -2,7 +2,7 @@
 #include <thread>
 #include <future>
 
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 
 #include <Poco/DirectoryIterator.h>
 #include <Poco/FileStream.h>

libs/libcommon/include/common/threadpool.hpp

@@ -0,0 +1,28 @@
+/*! \file
+* \brief Main include.
+*
+* This is the only file you have to include in order to use the 
+* complete threadpool library.
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+#ifndef THREADPOOL_HPP_INCLUDED
+#define THREADPOOL_HPP_INCLUDED
+
+#include "threadpool/future.hpp"
+#include "threadpool/pool.hpp"
+
+#include "threadpool/pool_adaptors.hpp"
+#include "threadpool/task_adaptors.hpp"
+
+
+#endif // THREADPOOL_HPP_INCLUDED
+

libs/libcommon/include/common/threadpool/detail/future.hpp

@@ -0,0 +1,215 @@
+/*! \file
+* \brief TODO.
+*
+* TODO. 
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_DETAIL_FUTURE_IMPL_HPP_INCLUDED
+#define THREADPOOL_DETAIL_FUTURE_IMPL_HPP_INCLUDED
+
+
+#include "locking_ptr.hpp"
+
+#include <boost/smart_ptr.hpp>
+#include <boost/optional.hpp>
+#include <boost/thread/mutex.hpp>
+#include <boost/thread/condition.hpp>
+#include <boost/thread/xtime.hpp>
+#include <boost/utility/result_of.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/type_traits.hpp>
+
+namespace boost { namespace threadpool { namespace detail 
+{
+
+template<class Result> 
+class future_impl
+{
+public:
+  typedef Result const & result_type; //!< Indicates the functor's result type.
+
+  typedef Result future_result_type; //!< Indicates the future's result type.
+  typedef future_impl<future_result_type> future_type;
+
+private:
+    volatile bool m_ready;
+    volatile future_result_type m_result;
+
+    mutable mutex m_monitor;
+    mutable condition m_condition_ready;	
+
+    volatile bool m_is_cancelled;
+    volatile bool m_executing;
+
+public:
+
+
+public:
+
+  future_impl()
+  : m_ready(false)
+  , m_is_cancelled(false)
+  {
+  }
+
+  bool ready() const volatile
+  {
+    return m_ready; 
+  }
+
+  void wait() const volatile
+  {
+    const future_type* self = const_cast<const future_type*>(this);
+    mutex::scoped_lock lock(self->m_monitor);
+
+    while(!m_ready)
+    {
+      self->m_condition_ready.wait(lock);
+    }
+  }
+
+
+  bool timed_wait(boost::xtime const & timestamp) const
+  {
+    const future_type* self = const_cast<const future_type*>(this);
+    mutex::scoped_lock lock(self->m_monitor);
+
+    while(!m_ready)
+    {
+      if(!self->m_condition_ready.timed_wait(lock, timestamp)) return false;
+    }
+
+    return true;
+  }
+
+
+  result_type operator()() const volatile
+  {
+    wait();
+/*
+    if( throw_exception_ != 0 )
+    {
+      throw_exception_( this );
+    }
+*/
+ 
+    return *(const_cast<const future_result_type*>(&m_result));
+  }
+
+
+  void set_value(future_result_type const & r) volatile
+  {
+    locking_ptr<future_type, mutex> lockedThis(*this, m_monitor);
+    if(!m_ready && !m_is_cancelled)
+    {
+      lockedThis->m_result = r;
+      lockedThis->m_ready = true;
+      lockedThis->m_condition_ready.notify_all();
+    }
+  }
+/*
+  template<class E> void set_exception() // throw()
+  {
+    m_impl->template set_exception<E>();
+  }
+
+  template<class E> void set_exception( char const * what ) // throw()
+  {
+    m_impl->template set_exception<E>( what );
+  }
+  */
+
+
+   bool cancel() volatile
+   {
+     if(!m_ready || m_executing)
+     {
+        m_is_cancelled = true;
+        return true;
+     }
+     else
+     {
+       return false;
+     }
+   }
+
+
+   bool is_cancelled() const volatile
+   {
+     return m_is_cancelled;
+   }
+
+
+   void set_execution_status(bool executing) volatile
+   {
+     m_executing = executing;
+   }
+};
+
+
+template<
+  template <typename> class Future,
+  typename Function
+>
+class future_impl_task_func
+{
+
+public:
+  typedef void result_type;                         //!< Indicates the functor's result type.
+
+  typedef Function function_type;                   //!< Indicates the function's type.
+  typedef typename result_of<function_type()>::type future_result_type; //!< Indicates the future's result type.
+  typedef Future<future_result_type> future_type;   //!< Indicates the future's type.
+
+  // The task is required to be a nullary function.
+  BOOST_STATIC_ASSERT(function_traits<function_type()>::arity == 0);
+
+  // The task function's result type is required not to be void.
+  BOOST_STATIC_ASSERT(!is_void<future_result_type>::value);
+
+private:
+  function_type             m_function;
+  shared_ptr<future_type>   m_future;
+
+public:
+  future_impl_task_func(function_type const & function, shared_ptr<future_type> const & future)
+  : m_function(function)
+  , m_future(future)
+  {
+  }
+
+  void operator()()
+  {
+    if(m_function)
+    {
+      m_future->set_execution_status(true);
+      if(!m_future->is_cancelled())
+      {
+        // TODO future exeception handling 
+        m_future->set_value(m_function());
+      }
+      m_future->set_execution_status(false); // TODO consider exceptions
+    }
+  }
+
+};
+
+
+
+
+
+} } } // namespace boost::threadpool::detail
+
+#endif // THREADPOOL_DETAIL_FUTURE_IMPL_HPP_INCLUDED
+
+

libs/libcommon/include/common/threadpool/detail/locking_ptr.hpp

@@ -0,0 +1,102 @@
+/*! \file
+* \brief The locking_ptr is smart pointer with a scoped locking mechanism.
+*
+* The class is a wrapper for a volatile pointer. It enables synchronized access to the
+* internal pointer by locking the passed mutex.
+* locking_ptr is based on Andrei Alexandrescu's LockingPtr. For more information
+* see article "volatile - Multithreaded Programmer's Best Friend" by A. Alexandrescu.
+*
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_DETAIL_LOCKING_PTR_HPP_INCLUDED
+#define THREADPOOL_DETAIL_LOCKING_PTR_HPP_INCLUDED
+
+#include <boost/utility.hpp>
+
+// Support for old boost::thread
+//**********************************************
+#include <boost/thread/mutex.hpp>
+#ifndef BOOST_THREAD_MUTEX_HPP
+#include <boost/thread/detail/lock.hpp>
+#endif
+//**********************************************
+
+namespace boost { namespace threadpool { namespace detail 
+{
+
+/*! \brief  Smart pointer with a scoped locking mechanism.
+ *
+ * This class is a wrapper for a volatile pointer. It enables synchronized access to the
+ * internal pointer by locking the passed mutex.
+ */
+  template <typename T, typename Mutex>
+  class locking_ptr 
+  : private noncopyable
+  {
+    T* m_obj;                     //!< The instance pointer. 
+    Mutex & m_mutex;              //!< Mutex is used for scoped locking.
+
+  public:
+    /// Constructor.
+    locking_ptr(volatile T& obj, const volatile Mutex& mtx)
+      : m_obj(const_cast<T*>(&obj))
+      , m_mutex(*const_cast<Mutex*>(&mtx))
+    {   
+      // Lock mutex
+
+#ifndef BOOST_THREAD_MUTEX_HPP
+      // Support for old boost::thread
+      boost::detail::thread::lock_ops<Mutex>::lock(m_mutex);   
+#else 
+      m_mutex.lock();
+#endif
+    }
+
+
+    /// Destructor.
+    ~locking_ptr()
+    { 
+      // Unlock mutex
+#ifndef BOOST_THREAD_MUTEX_HPP
+      // Support for old boost::thread
+      boost::detail::thread::lock_ops<Mutex>::unlock(m_mutex);   
+#else 
+      m_mutex.unlock();
+#endif
+    }
+
+
+    /*! Returns a reference to the stored instance.
+    * \return The instance's reference.
+    */
+    T& operator*() const
+    {    
+      return *m_obj;    
+    }
+
+
+    /*! Returns a pointer to the stored instance.
+    * \return The instance's pointer.
+    */
+    T* operator->() const
+    {   
+      return m_obj;   
+    }
+  };
+
+
+} } } // namespace boost::threadpool::detail
+
+
+#endif // THREADPOOL_DETAIL_LOCKING_PTR_HPP_INCLUDED
+

libs/libcommon/include/common/threadpool/detail/pool_core.hpp

@@ -0,0 +1,453 @@
+/*! \file
+* \brief Thread pool core.
+*
+* This file contains the threadpool's core class: pool<Task, SchedulingPolicy>.
+*
+* Thread pools are a mechanism for asynchronous and parallel processing 
+* within the same process. The pool class provides a convenient way 
+* for dispatching asynchronous tasks as functions objects. The scheduling
+* of these tasks can be easily controlled by using customized schedulers. 
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_POOL_CORE_HPP_INCLUDED
+#define THREADPOOL_POOL_CORE_HPP_INCLUDED
+
+
+
+
+#include "locking_ptr.hpp"
+#include "worker_thread.hpp"
+
+#include "../task_adaptors.hpp"
+
+#include <boost/thread.hpp>
+#include <boost/thread/exceptions.hpp>
+#include <boost/thread/mutex.hpp>
+#include <boost/thread/condition.hpp>
+#include <boost/smart_ptr.hpp>
+#include <boost/bind.hpp>
+#include <boost/static_assert.hpp>
+#include <boost/type_traits.hpp>
+
+#include <vector>
+
+
+/// The namespace threadpool contains a thread pool and related utility classes.
+namespace boost { namespace threadpool { namespace detail 
+{
+
+  /*! \brief Thread pool. 
+  *
+  * Thread pools are a mechanism for asynchronous and parallel processing 
+  * within the same process. The pool class provides a convenient way 
+  * for dispatching asynchronous tasks as functions objects. The scheduling
+  * of these tasks can be easily controlled by using customized schedulers. 
+  * A task must not throw an exception.
+  *
+  * A pool_impl is DefaultConstructible and NonCopyable.
+  *
+  * \param Task A function object which implements the operator 'void operator() (void) const'. The operator () is called by the pool to execute the task. Exceptions are ignored.
+  * \param Scheduler A task container which determines how tasks are scheduled. It is guaranteed that this container is accessed only by one thread at a time. The scheduler shall not throw exceptions.
+  *
+  * \remarks The pool class is thread-safe.
+  * 
+  * \see Tasks: task_func, prio_task_func
+  * \see Scheduling policies: fifo_scheduler, lifo_scheduler, prio_scheduler
+  */ 
+  template <
+    typename Task, 
+
+    template <typename> class SchedulingPolicy,
+    template <typename> class SizePolicy,
+    template <typename> class SizePolicyController,
+    template <typename> class ShutdownPolicy
+  > 
+  class pool_core
+  : public enable_shared_from_this< pool_core<Task, SchedulingPolicy, SizePolicy, SizePolicyController, ShutdownPolicy > > 
+  , private noncopyable
+  {
+
+  public: // Type definitions
+    typedef Task task_type;                                 //!< Indicates the task's type.
+    typedef SchedulingPolicy<task_type> scheduler_type;     //!< Indicates the scheduler's type.
+    typedef pool_core<Task, 
+                      SchedulingPolicy, 
+                      SizePolicy,
+                      SizePolicyController,
+                      ShutdownPolicy > pool_type;           //!< Indicates the thread pool's type.
+    typedef SizePolicy<pool_type> size_policy_type;         //!< Indicates the sizer's type.
+    //typedef typename size_policy_type::size_controller size_controller_type;
+
+    typedef SizePolicyController<pool_type> size_controller_type;
+
+//    typedef SizePolicy<pool_type>::size_controller size_controller_type;
+    typedef ShutdownPolicy<pool_type> shutdown_policy_type;//!< Indicates the shutdown policy's type.  
+
+    typedef worker_thread<pool_type> worker_type;
+
+    // The task is required to be a nullary function.
+    BOOST_STATIC_ASSERT(function_traits<task_type()>::arity == 0);
+
+    // The task function's result type is required to be void.
+    BOOST_STATIC_ASSERT(is_void<typename result_of<task_type()>::type >::value);
+
+
+  private:  // Friends 
+    friend class worker_thread<pool_type>;
+
+#if defined(__SUNPRO_CC) && (__SUNPRO_CC <= 0x580)  // Tested with CC: Sun C++ 5.8 Patch 121018-08 2006/12/06
+   friend class SizePolicy;
+   friend class ShutdownPolicy;
+#else
+   friend class SizePolicy<pool_type>;
+   friend class ShutdownPolicy<pool_type>;
+#endif
+
+  private: // The following members may be accessed by _multiple_ threads at the same time:
+    volatile size_t m_worker_count;	
+    volatile size_t m_target_worker_count;	
+    volatile size_t m_active_worker_count;
+      
+
+
+  private: // The following members are accessed only by _one_ thread at the same time:
+    scheduler_type  m_scheduler;
+    scoped_ptr<size_policy_type> m_size_policy; // is never null
+    
+    bool  m_terminate_all_workers;								// Indicates if termination of all workers was triggered.
+    std::vector<shared_ptr<worker_type> > m_terminated_workers; // List of workers which are terminated but not fully destructed.
+    
+  private: // The following members are implemented thread-safe:
+    mutable recursive_mutex  m_monitor;
+    mutable condition m_worker_idle_or_terminated_event;	// A worker is idle or was terminated.
+    mutable condition m_task_or_terminate_workers_event;  // Task is available OR total worker count should be reduced.
+
+  public:
+    /// Constructor.
+    pool_core()
+      : m_worker_count(0) 
+      , m_target_worker_count(0)
+      , m_active_worker_count(0)
+      , m_terminate_all_workers(false)
+    {
+      pool_type volatile & self_ref = *this;
+      m_size_policy.reset(new size_policy_type(self_ref));
+
+      m_scheduler.clear();
+    }
+
+
+    /// Destructor.
+    ~pool_core()
+    {
+    }
+
+    /*! Gets the size controller which manages the number of threads in the pool. 
+    * \return The size controller.
+    * \see SizePolicy
+    */
+    size_controller_type size_controller()
+    {
+      return size_controller_type(*m_size_policy, this->shared_from_this());
+    }
+
+    /*! Gets the number of threads in the pool.
+    * \return The number of threads.
+    */
+    size_t size()	const volatile
+    {
+      return m_worker_count;
+    }
+
+// TODO is only called once
+    void shutdown()
+    {
+      ShutdownPolicy<pool_type>::shutdown(*this);
+    }
+
+    /*! Schedules a task for asynchronous execution. The task will be executed once only.
+    * \param task The task function object. It should not throw execeptions.
+    * \return true, if the task could be scheduled and false otherwise. 
+    */  
+    bool schedule(task_type const & task) volatile
+    {	
+      locking_ptr<pool_type, recursive_mutex> lockedThis(*this, m_monitor); 
+      
+      if(lockedThis->m_scheduler.push(task))
+      {
+        lockedThis->m_task_or_terminate_workers_event.notify_one();
+        return true;
+      }
+      else
+      {
+        return false;
+      }
+    }	
+
+
+    /*! Returns the number of tasks which are currently executed.
+    * \return The number of active tasks. 
+    */  
+    size_t active() const volatile
+    {
+      return m_active_worker_count;
+    }
+
+
+    /*! Returns the number of tasks which are ready for execution.    
+    * \return The number of pending tasks. 
+    */  
+    size_t pending() const volatile
+    {
+      locking_ptr<const pool_type, recursive_mutex> lockedThis(*this, m_monitor);
+      return lockedThis->m_scheduler.size();
+    }
+
+
+    /*! Removes all pending tasks from the pool's scheduler.
+    */  
+    void clear() volatile
+    { 
+      locking_ptr<pool_type, recursive_mutex> lockedThis(*this, m_monitor);
+      lockedThis->m_scheduler.clear();
+    }    
+
+
+    /*! Indicates that there are no tasks pending. 
+    * \return true if there are no tasks ready for execution.	
+    * \remarks This function is more efficient that the check 'pending() == 0'.
+    */   
+    bool empty() const volatile
+    {
+      locking_ptr<const pool_type, recursive_mutex> lockedThis(*this, m_monitor);
+      return lockedThis->m_scheduler.empty();
+    }	
+
+
+    /*! The current thread of execution is blocked until the sum of all active
+    *  and pending tasks is equal or less than a given threshold. 
+    * \param task_threshold The maximum number of tasks in pool and scheduler.
+    */     
+    void wait(size_t const task_threshold = 0) const volatile
+    {
+      const pool_type* self = const_cast<const pool_type*>(this);
+      recursive_mutex::scoped_lock lock(self->m_monitor);
+
+      if(0 == task_threshold)
+      {
+        while(0 != self->m_active_worker_count || !self->m_scheduler.empty())
+        { 
+          self->m_worker_idle_or_terminated_event.wait(lock);
+        }
+      }
+      else
+      {
+        while(task_threshold < self->m_active_worker_count + self->m_scheduler.size())
+        { 
+          self->m_worker_idle_or_terminated_event.wait(lock);
+        }
+      }
+    }	
+
+    /*! The current thread of execution is blocked until the timestamp is met
+    * or the sum of all active and pending tasks is equal or less 
+    * than a given threshold.  
+    * \param timestamp The time when function returns at the latest.
+    * \param task_threshold The maximum number of tasks in pool and scheduler.
+    * \return true if the task sum is equal or less than the threshold, false otherwise.
+    */       
+    bool wait(xtime const & timestamp, size_t const task_threshold = 0) const volatile
+    {
+      const pool_type* self = const_cast<const pool_type*>(this);
+      recursive_mutex::scoped_lock lock(self->m_monitor);
+
+      if(0 == task_threshold)
+      {
+        while(0 != self->m_active_worker_count || !self->m_scheduler.empty())
+        { 
+          if(!self->m_worker_idle_or_terminated_event.timed_wait(lock, timestamp)) return false;
+        }
+      }
+      else
+      {
+        while(task_threshold < self->m_active_worker_count + self->m_scheduler.size())
+        { 
+          if(!self->m_worker_idle_or_terminated_event.timed_wait(lock, timestamp)) return false;
+        }
+      }
+
+      return true;
+    }
+
+
+  private:	
+
+
+    void terminate_all_workers(bool const wait) volatile
+    {
+      pool_type* self = const_cast<pool_type*>(this);
+      recursive_mutex::scoped_lock lock(self->m_monitor);
+
+      self->m_terminate_all_workers = true;
+
+      m_target_worker_count = 0;
+      self->m_task_or_terminate_workers_event.notify_all();
+
+      if(wait)
+      {
+        while(m_worker_count > 0)
+        {
+          self->m_worker_idle_or_terminated_event.wait(lock);
+        }
+
+        for(typename std::vector<shared_ptr<worker_type> >::iterator it = self->m_terminated_workers.begin();
+          it != self->m_terminated_workers.end();
+          ++it)
+        {
+          (*it)->join();
+        }
+        self->m_terminated_workers.clear();
+      }
+    }
+
+
+    /*! Changes the number of worker threads in the pool. The resizing 
+    *  is handled by the SizePolicy.
+    * \param threads The new number of worker threads.
+    * \return true, if pool will be resized and false if not. 
+    */
+    bool resize(size_t const worker_count) volatile
+    {
+      locking_ptr<pool_type, recursive_mutex> lockedThis(*this, m_monitor); 
+
+      if(!m_terminate_all_workers)
+      {
+        m_target_worker_count = worker_count;
+      }
+      else
+      { 
+        return false;
+      }
+
+
+      if(m_worker_count <= m_target_worker_count)
+      { // increase worker count
+        while(m_worker_count < m_target_worker_count)
+        {
+          try
+          {
+            worker_thread<pool_type>::create_and_attach(lockedThis->shared_from_this());
+            m_worker_count++;
+            m_active_worker_count++;	
+          }
+          catch(thread_resource_error)
+          {
+            return false;
+          }
+        }
+      }
+      else
+      { // decrease worker count
+        lockedThis->m_task_or_terminate_workers_event.notify_all();   // TODO: Optimize number of notified workers
+      }
+
+      return true;
+    }
+
+
+    // worker died with unhandled exception
+    void worker_died_unexpectedly(shared_ptr<worker_type> worker) volatile
+    {
+      locking_ptr<pool_type, recursive_mutex> lockedThis(*this, m_monitor);
+
+      m_worker_count--;
+      m_active_worker_count--;
+      lockedThis->m_worker_idle_or_terminated_event.notify_all();	
+
+      if(m_terminate_all_workers)
+      {
+        lockedThis->m_terminated_workers.push_back(worker);
+      }
+      else
+      {
+        lockedThis->m_size_policy->worker_died_unexpectedly(m_worker_count);
+      }
+    }
+
+    void worker_destructed(shared_ptr<worker_type> worker) volatile
+    {
+      locking_ptr<pool_type, recursive_mutex> lockedThis(*this, m_monitor);
+      m_worker_count--;
+      m_active_worker_count--;
+      lockedThis->m_worker_idle_or_terminated_event.notify_all();	
+
+      if(m_terminate_all_workers)
+      {
+        lockedThis->m_terminated_workers.push_back(worker);
+      }
+    }
+
+
+    bool execute_task() volatile
+    {
+      function0<void> task;
+
+      { // fetch task
+        pool_type* lockedThis = const_cast<pool_type*>(this);
+        recursive_mutex::scoped_lock lock(lockedThis->m_monitor);
+
+        // decrease number of threads if necessary
+        if(m_worker_count > m_target_worker_count)
+        {	
+          return false;	// terminate worker
+        }
+
+
+        // wait for tasks
+        while(lockedThis->m_scheduler.empty())
+        {	
+          // decrease number of workers if necessary
+          if(m_worker_count > m_target_worker_count)
+          {	
+            return false;	// terminate worker
+          }
+          else
+          {
+            m_active_worker_count--;
+            lockedThis->m_worker_idle_or_terminated_event.notify_all();	
+            lockedThis->m_task_or_terminate_workers_event.wait(lock);
+            m_active_worker_count++;
+          }
+        }
+
+        task = lockedThis->m_scheduler.top();
+        lockedThis->m_scheduler.pop();
+      }
+
+      // call task function
+      if(task)
+      {
+        task();
+      }
+ 
+      //guard->disable();
+      return true;
+    }
+  };
+
+
+
+
+} } } // namespace boost::threadpool::detail
+
+#endif // THREADPOOL_POOL_CORE_HPP_INCLUDED

libs/libcommon/include/common/threadpool/detail/scope_guard.hpp

@@ -0,0 +1,65 @@
+/*! \file
+* \brief TODO.
+*
+* TODO. 
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_DETAIL_SCOPE_GUARD_HPP_INCLUDED
+#define THREADPOOL_DETAIL_SCOPE_GUARD_HPP_INCLUDED
+
+
+
+#include <boost/function.hpp>
+
+
+namespace boost { namespace threadpool { namespace detail 
+{
+
+// TODO documentation
+class scope_guard
+: private boost::noncopyable
+{
+	function0<void> const m_function;
+	bool                  m_is_active;
+
+public:
+	scope_guard(function0<void> const & call_on_exit)
+	: m_function(call_on_exit)
+	, m_is_active(true)
+	{
+	}
+
+	~scope_guard()
+	{
+		if(m_is_active && m_function)
+		{
+			m_function();
+		}
+	}
+
+	void disable()
+	{
+		m_is_active = false;
+	}
+};
+
+
+
+
+
+
+} } } // namespace boost::threadpool::detail
+
+#endif // THREADPOOL_DETAIL_SCOPE_GUARD_HPP_INCLUDED
+
+

libs/libcommon/include/common/threadpool/detail/worker_thread.hpp

@@ -0,0 +1,115 @@
+/*! \file
+* \brief Thread pool worker.
+*
+* The worker thread instance is attached to a pool 
+* and executes tasks of this pool. 
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+#ifndef THREADPOOL_DETAIL_WORKER_THREAD_HPP_INCLUDED
+#define THREADPOOL_DETAIL_WORKER_THREAD_HPP_INCLUDED
+
+
+#include "scope_guard.hpp"
+
+#include <boost/smart_ptr.hpp>
+#include <boost/thread.hpp>
+#include <boost/thread/exceptions.hpp>
+#include <boost/thread/mutex.hpp>
+#include <boost/bind.hpp>
+
+
+namespace boost { namespace threadpool { namespace detail 
+{
+
+  /*! \brief Thread pool worker. 
+  *
+  * A worker_thread represents a thread of execution. The worker is attached to a 
+  * thread pool and processes tasks of that pool. The lifetime of the worker and its 
+  * internal boost::thread is managed automatically.
+  *
+  * This class is a helper class and cannot be constructed or accessed directly.
+  * 
+  * \see pool_core
+  */ 
+  template <typename Pool>
+  class worker_thread
+  : public enable_shared_from_this< worker_thread<Pool> > 
+  , private noncopyable
+  {
+  public:
+    typedef Pool pool_type;         	   //!< Indicates the pool's type.
+
+  private:
+    shared_ptr<pool_type>      m_pool;     //!< Pointer to the pool which created the worker.
+    shared_ptr<boost::thread>  m_thread;   //!< Pointer to the thread which executes the run loop.
+
+    
+    /*! Constructs a new worker. 
+    * \param pool Pointer to it's parent pool.
+    * \see function create_and_attach
+    */
+    worker_thread(shared_ptr<pool_type> const & pool)
+    : m_pool(pool)
+    {
+      assert(pool);
+    }
+
+	
+	/*! Notifies that an exception occurred in the run loop.
+	*/
+	void died_unexpectedly()
+	{
+		m_pool->worker_died_unexpectedly(this->shared_from_this());
+	}
+
+
+  public:
+	  /*! Executes pool's tasks sequentially.
+	  */
+	  void run()
+	  { 
+		  scope_guard notify_exception(bind(&worker_thread::died_unexpectedly, this));
+
+		  while(m_pool->execute_task()) {}
+
+		  notify_exception.disable();
+		  m_pool->worker_destructed(this->shared_from_this());
+	  }
+
+
+	  /*! Joins the worker's thread.
+	  */
+	  void join()
+	  {
+		  m_thread->join();
+	  }
+
+
+	  /*! Constructs a new worker thread and attaches it to the pool.
+	  * \param pool Pointer to the pool.
+	  */
+	  static void create_and_attach(shared_ptr<pool_type> const & pool)
+	  {
+		  shared_ptr<worker_thread> worker(new worker_thread(pool));
+		  if(worker)
+		  {
+			  worker->m_thread.reset(new boost::thread(bind(&worker_thread::run, worker)));
+		  }
+	  }
+
+  };
+
+
+} } } // namespace boost::threadpool::detail
+
+#endif // THREADPOOL_DETAIL_WORKER_THREAD_HPP_INCLUDED
+

libs/libcommon/include/common/threadpool/future.hpp

@@ -0,0 +1,144 @@
+/*! \file
+* \brief TODO.
+*
+* TODO. 
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+#ifndef THREADPOOL_FUTURE_HPP_INCLUDED
+#define THREADPOOL_FUTURE_HPP_INCLUDED
+
+
+  
+#include "detail/future.hpp"
+#include <boost/utility/enable_if.hpp>
+
+//#include "pool.hpp"
+//#include <boost/utility.hpp>
+
+//#include <boost/thread/mutex.hpp>
+
+
+namespace boost { namespace threadpool
+{
+
+  /*! \brief Experimental. Do not use in production code. TODO. 
+  *
+  * TODO Future
+  *
+  * \see TODO
+  *
+  */ 
+
+
+template<class Result> 
+class future
+{
+private:
+  shared_ptr<detail::future_impl<Result> > m_impl;
+
+public:
+    typedef Result const & result_type; //!< Indicates the functor's result type.
+    typedef Result future_result_type; //!< Indicates the future's result type.
+
+
+public:
+
+  future()
+  : m_impl(new detail::future_impl<future_result_type>()) // TODO remove this
+  {
+  }
+
+  // only for internal usage
+  future(shared_ptr<detail::future_impl<Result> > const & impl)
+  : m_impl(impl)
+  {
+  }
+
+  bool ready() const
+  {
+    return m_impl->ready();
+  }
+
+  void wait() const
+  {
+    m_impl->wait();
+  }
+
+  bool timed_wait(boost::xtime const & timestamp) const
+  {
+    return m_impl->timed_wait(timestamp);
+  }
+
+   result_type operator()() // throw( thread::cancelation_exception, ... )
+   {
+     return (*m_impl)();
+   }
+
+   result_type get() // throw( thread::cancelation_exception, ... )
+   {
+     return (*m_impl)();
+   }
+
+   bool cancel()
+   {
+     return m_impl->cancel();
+   }
+
+   bool is_cancelled() const
+   {
+     return m_impl->is_cancelled();
+   }
+};
+
+
+
+
+
+template<class Pool, class Function>
+typename disable_if < 
+  is_void< typename result_of< Function() >::type >,
+  future< typename result_of< Function() >::type >
+>::type
+schedule(Pool& pool, const Function& task)
+{
+  typedef typename result_of< Function() >::type future_result_type;
+
+  // create future impl and future
+  shared_ptr<detail::future_impl<future_result_type> > impl(new detail::future_impl<future_result_type>);
+  future <future_result_type> res(impl);
+
+  // schedule future impl
+  pool.schedule(detail::future_impl_task_func<detail::future_impl, Function>(task, impl));
+
+  // return future
+  return res;
+
+/*
+ TODO
+  if(pool->schedule(bind(&Future::run, future)))
+  {
+    return future;
+  }
+  else
+  {
+    // construct empty future
+    return error_future;
+  }
+  */
+}
+
+
+
+} } // namespace boost::threadpool
+
+#endif // THREADPOOL_FUTURE_HPP_INCLUDED
+

libs/libcommon/include/common/threadpool/pool.hpp

@@ -0,0 +1,232 @@
+/*! \file
+* \brief Thread pool core.
+*
+* This file contains the threadpool's core class: pool<Task, SchedulingPolicy>.
+*
+* Thread pools are a mechanism for asynchronous and parallel processing 
+* within the same process. The pool class provides a convenient way 
+* for dispatching asynchronous tasks as functions objects. The scheduling
+* of these tasks can be easily controlled by using customized schedulers. 
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_POOL_HPP_INCLUDED
+#define THREADPOOL_POOL_HPP_INCLUDED
+
+#include <boost/ref.hpp>
+
+#include "detail/pool_core.hpp"
+
+#include "task_adaptors.hpp"
+
+#include "detail/locking_ptr.hpp"
+
+#include "scheduling_policies.hpp"
+#include "size_policies.hpp"
+#include "shutdown_policies.hpp"
+
+
+
+/// The namespace threadpool contains a thread pool and related utility classes.
+namespace boost { namespace threadpool
+{
+
+
+
+  /*! \brief Thread pool. 
+  *
+  * Thread pools are a mechanism for asynchronous and parallel processing 
+  * within the same process. The pool class provides a convenient way 
+  * for dispatching asynchronous tasks as functions objects. The scheduling
+  * of these tasks can be easily controlled by using customized schedulers. 
+  * A task must not throw an exception.
+  *
+  * A pool is DefaultConstructible, CopyConstructible and Assignable.
+  * It has reference semantics; all copies of the same pool are equivalent and interchangeable. 
+  * All operations on a pool except assignment are strongly thread safe or sequentially consistent; 
+  * that is, the behavior of concurrent calls is as if the calls have been issued sequentially in an unspecified order.
+  *
+  * \param Task A function object which implements the operator 'void operator() (void) const'. The operator () is called by the pool to execute the task. Exceptions are ignored.
+  * \param SchedulingPolicy A task container which determines how tasks are scheduled. It is guaranteed that this container is accessed only by one thread at a time. The scheduler shall not throw exceptions.
+  *
+  * \remarks The pool class is thread-safe.
+  * 
+  * \see Tasks: task_func, prio_task_func
+  * \see Scheduling policies: fifo_scheduler, lifo_scheduler, prio_scheduler
+  */ 
+  template <
+    typename Task                                   = task_func,
+    template <typename> class SchedulingPolicy      = fifo_scheduler,
+    template <typename> class SizePolicy            = static_size,
+    template <typename> class SizePolicyController  = resize_controller,
+    template <typename> class ShutdownPolicy        = wait_for_all_tasks
+  > 
+  class thread_pool 
+  {
+    typedef detail::pool_core<Task, 
+                              SchedulingPolicy,
+                              SizePolicy,
+                              SizePolicyController,
+                              ShutdownPolicy> pool_core_type;
+    shared_ptr<pool_core_type>          m_core; // pimpl idiom
+    shared_ptr<void>                    m_shutdown_controller; // If the last pool holding a pointer to the core is deleted the controller shuts the pool down.
+
+  public: // Type definitions
+    typedef Task task_type;                                   //!< Indicates the task's type.
+    typedef SchedulingPolicy<task_type> scheduler_type;       //!< Indicates the scheduler's type.
+ /*   typedef thread_pool<Task, 
+                        SchedulingPolicy,
+                        SizePolicy,
+                        ShutdownPolicy > pool_type;          //!< Indicates the thread pool's type.
+ */
+    typedef SizePolicy<pool_core_type> size_policy_type; 
+    typedef SizePolicyController<pool_core_type> size_controller_type;
+
+
+  public:
+    /*! Constructor.
+     * \param initial_threads The pool is immediately resized to set the specified number of threads. The pool's actual number threads depends on the SizePolicy.
+     */
+    thread_pool(size_t initial_threads = 0)
+    : m_core(new pool_core_type)
+    , m_shutdown_controller(static_cast<void*>(0), bind(&pool_core_type::shutdown, m_core))
+    {
+      size_policy_type::init(*m_core, initial_threads);
+    }
+
+
+    /*! Gets the size controller which manages the number of threads in the pool. 
+    * \return The size controller.
+    * \see SizePolicy
+    */
+    size_controller_type size_controller()
+    {
+      return m_core->size_controller();
+    }
+
+
+    /*! Gets the number of threads in the pool.
+    * \return The number of threads.
+    */
+    size_t size()	const
+    {
+      return m_core->size();
+    }
+
+
+     /*! Schedules a task for asynchronous execution. The task will be executed once only.
+     * \param task The task function object. It should not throw execeptions.
+     * \return true, if the task could be scheduled and false otherwise. 
+     */  
+     bool schedule(task_type const & task)
+     {	
+       return m_core->schedule(task);
+     }
+
+
+    /*! Returns the number of tasks which are currently executed.
+    * \return The number of active tasks. 
+    */  
+    size_t active() const
+    {
+      return m_core->active();
+    }
+
+
+    /*! Returns the number of tasks which are ready for execution.    
+    * \return The number of pending tasks. 
+    */  
+    size_t pending() const
+    {
+      return m_core->pending();
+    }
+
+
+    /*! Removes all pending tasks from the pool's scheduler.
+    */  
+    void clear()
+    { 
+      m_core->clear();
+    }    
+
+
+    /*! Indicates that there are no tasks pending. 
+    * \return true if there are no tasks ready for execution.	
+    * \remarks This function is more efficient that the check 'pending() == 0'.
+    */   
+    bool empty() const
+    {
+      return m_core->empty();
+    }	
+
+
+    /*! The current thread of execution is blocked until the sum of all active
+    *  and pending tasks is equal or less than a given threshold. 
+    * \param task_threshold The maximum number of tasks in pool and scheduler.
+    */     
+    void wait(size_t task_threshold = 0) const
+    {
+      m_core->wait(task_threshold);
+    }	
+
+
+    /*! The current thread of execution is blocked until the timestamp is met
+    * or the sum of all active and pending tasks is equal or less 
+    * than a given threshold.  
+    * \param timestamp The time when function returns at the latest.
+    * \param task_threshold The maximum number of tasks in pool and scheduler.
+    * \return true if the task sum is equal or less than the threshold, false otherwise.
+    */       
+    bool wait(xtime const & timestamp, size_t task_threshold = 0) const
+    {
+      return m_core->wait(timestamp, task_threshold);
+    }
+  };
+
+
+
+  /*! \brief Fifo pool.
+  *
+  * The pool's tasks are fifo scheduled task_func functors.
+  *
+  */ 
+  typedef thread_pool<task_func, fifo_scheduler, static_size, resize_controller, wait_for_all_tasks> fifo_pool;
+
+
+  /*! \brief Lifo pool.
+  *
+  * The pool's tasks are lifo scheduled task_func functors.
+  *
+  */ 
+  typedef thread_pool<task_func, lifo_scheduler, static_size, resize_controller, wait_for_all_tasks> lifo_pool;
+
+
+  /*! \brief Pool for prioritized task.
+  *
+  * The pool's tasks are prioritized prio_task_func functors.
+  *
+  */ 
+  typedef thread_pool<prio_task_func, prio_scheduler, static_size, resize_controller, wait_for_all_tasks> prio_pool;
+
+
+  /*! \brief A standard pool.
+  *
+  * The pool's tasks are fifo scheduled task_func functors.
+  *
+  */ 
+  typedef fifo_pool pool;
+
+
+
+} } // namespace boost::threadpool
+
+#endif // THREADPOOL_POOL_HPP_INCLUDED

libs/libcommon/include/common/threadpool/pool_adaptors.hpp

@@ -0,0 +1,70 @@
+/*! \file
+* \brief Pool adaptors.
+*
+* This file contains an easy-to-use adaptor similar to a smart 
+* pointer for the pool class. 
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_POOL_ADAPTORS_HPP_INCLUDED
+#define THREADPOOL_POOL_ADAPTORS_HPP_INCLUDED
+
+#include <boost/smart_ptr.hpp>
+
+
+namespace boost { namespace threadpool
+{
+
+
+// TODO convenience scheduling function
+    /*! Schedules a Runnable for asynchronous execution. A Runnable is an arbitrary class with a run()
+    * member function. This a convenience shorthand for pool->schedule(bind(&Runnable::run, task_object)).
+    * \param 
+    * \param obj The Runnable object. The member function run() will be exectued and should not throw execeptions.
+    * \return true, if the task could be scheduled and false otherwise. 
+    */  
+    template<typename Pool, typename Runnable>
+    bool schedule(Pool& pool, shared_ptr<Runnable> const & obj)
+    {	
+      return pool->schedule(bind(&Runnable::run, obj));
+    }	
+    
+    /*! Schedules a task for asynchronous execution. The task will be executed once only.
+    * \param task The task function object.
+    */  
+    template<typename Pool>
+    typename enable_if < 
+      is_void< typename result_of< typename Pool::task_type() >::type >,
+      bool
+    >::type
+    schedule(Pool& pool, typename Pool::task_type const & task)
+    {	
+      return pool.schedule(task);
+    }	
+
+
+    template<typename Pool>
+    typename enable_if < 
+      is_void< typename result_of< typename Pool::task_type() >::type >,
+      bool
+    >::type
+    schedule(shared_ptr<Pool> const pool, typename Pool::task_type const & task)
+    {	
+      return pool->schedule(task);
+    }	
+
+
+} } // namespace boost::threadpool
+
+#endif // THREADPOOL_POOL_ADAPTORS_HPP_INCLUDED
+
+

libs/libcommon/include/common/threadpool/scheduling_policies.hpp

@@ -0,0 +1,262 @@
+/*! \file
+* \brief Task scheduling policies.
+*
+* This file contains some fundamental scheduling policies for the pool class. 
+* A scheduling policy is realized by a task container which controls the access to
+* the tasks. 	Fundamentally the container determines the order the tasks are processed
+* by the thread pool. 
+* The task containers need not to be thread-safe because they are used by the pool 
+* in thread-safe way. 
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_SCHEDULING_POLICIES_HPP_INCLUDED
+#define THREADPOOL_SCHEDULING_POLICIES_HPP_INCLUDED
+
+
+#include <queue>
+#include <deque>
+
+#include "task_adaptors.hpp"
+
+namespace boost { namespace threadpool
+{
+
+  /*! \brief SchedulingPolicy which implements FIFO ordering. 
+  *
+  * This container implements a FIFO scheduling policy.
+  * The first task to be added to the scheduler will be the first to be removed.
+  * The processing proceeds sequentially in the same order. 
+  * FIFO stands for "first in, first out".
+  *
+  * \param Task A function object which implements the operator()(void).
+  *
+  */ 
+  template <typename Task = task_func>  
+  class fifo_scheduler
+  {
+  public:
+    typedef Task task_type; //!< Indicates the scheduler's task type.
+
+  protected:
+    std::deque<task_type> m_container;  //!< Internal task container.	
+
+
+  public:
+    /*! Adds a new task to the scheduler.
+    * \param task The task object.
+    * \return true, if the task could be scheduled and false otherwise. 
+    */
+    bool push(task_type const & task)
+    {
+      m_container.push_back(task);
+      return true;
+    }
+
+    /*! Removes the task which should be executed next.
+    */
+    void pop()
+    {
+      m_container.pop_front();
+    }
+
+    /*! Gets the task which should be executed next.
+    *  \return The task object to be executed.
+    */
+    task_type const & top() const
+    {
+      return m_container.front();
+    }
+
+    /*! Gets the current number of tasks in the scheduler.
+    *  \return The number of tasks.
+    *  \remarks Prefer empty() to size() == 0 to check if the scheduler is empty.
+    */
+    size_t size() const
+    {
+      return m_container.size();
+    }
+
+    /*! Checks if the scheduler is empty.
+    *  \return true if the scheduler contains no tasks, false otherwise.
+    *  \remarks Is more efficient than size() == 0. 
+    */
+    bool empty() const
+    {
+      return m_container.empty();
+    }
+
+    /*! Removes all tasks from the scheduler.
+    */  
+    void clear()
+    {   
+      m_container.clear();
+    } 
+  };
+
+
+
+  /*! \brief SchedulingPolicy which implements LIFO ordering. 
+  *
+  * This container implements a LIFO scheduling policy.
+  * The last task to be added to the scheduler will be the first to be removed.
+  * LIFO stands for "last in, first out".
+  *
+  * \param Task A function object which implements the operator()(void).
+  *
+  */ 
+  template <typename Task = task_func>  
+  class lifo_scheduler
+  {
+  public:
+    typedef Task task_type;  //!< Indicates the scheduler's task type.
+
+  protected:
+    std::deque<task_type> m_container;  //!< Internal task container.	
+
+  public:
+    /*! Adds a new task to the scheduler.
+    * \param task The task object.
+    * \return true, if the task could be scheduled and false otherwise. 
+    */
+    bool push(task_type const & task)
+    {
+      m_container.push_front(task);
+      return true;
+    }
+
+    /*! Removes the task which should be executed next.
+    */
+    void pop()
+    {
+      m_container.pop_front();
+    }
+
+    /*! Gets the task which should be executed next.
+    *  \return The task object to be executed.
+    */
+    task_type const & top() const
+    {
+      return m_container.front();
+    }
+
+    /*! Gets the current number of tasks in the scheduler.
+    *  \return The number of tasks.
+    *  \remarks Prefer empty() to size() == 0 to check if the scheduler is empty.
+    */
+    size_t size() const
+    {
+      return m_container.size();
+    }
+
+    /*! Checks if the scheduler is empty.
+    *  \return true if the scheduler contains no tasks, false otherwise.
+    *  \remarks Is more efficient than size() == 0. 
+    */
+    bool empty() const
+    {
+      return m_container.empty();
+    }
+
+    /*! Removes all tasks from the scheduler.
+    */  
+    void clear()
+    {    
+      m_container.clear();
+    } 
+
+  };
+
+
+
+  /*! \brief SchedulingPolicy which implements prioritized ordering. 
+  *
+  * This container implements a scheduling policy based on task priorities.
+  * The task with highest priority will be the first to be removed.
+  * It must be possible to compare two tasks using operator<. 
+  *
+  * \param Task A function object which implements the operator() and operator<. operator< must be a partial ordering.
+  *
+  * \see prio_thread_func
+  *
+  */ 
+  template <typename Task = prio_task_func>  
+  class prio_scheduler
+  {
+  public:
+    typedef Task task_type; //!< Indicates the scheduler's task type.
+
+  protected:
+    std::priority_queue<task_type> m_container;  //!< Internal task container.
+
+
+  public:
+    /*! Adds a new task to the scheduler.
+    * \param task The task object.
+    * \return true, if the task could be scheduled and false otherwise. 
+    */
+    bool push(task_type const & task)
+    {
+      m_container.push(task);
+      return true;
+    }
+
+    /*! Removes the task which should be executed next.
+    */
+    void pop()
+    {
+      m_container.pop();
+    }
+
+    /*! Gets the task which should be executed next.
+    *  \return The task object to be executed.
+    */
+    task_type const & top() const
+    {
+      return m_container.top();
+    }
+
+    /*! Gets the current number of tasks in the scheduler.
+    *  \return The number of tasks.
+    *  \remarks Prefer empty() to size() == 0 to check if the scheduler is empty.
+    */
+    size_t size() const
+    {
+      return m_container.size();
+    }
+
+    /*! Checks if the scheduler is empty.
+    *  \return true if the scheduler contains no tasks, false otherwise.
+    *  \remarks Is more efficient than size() == 0. 
+    */
+    bool empty() const
+    {
+      return m_container.empty();
+    }
+
+    /*! Removes all tasks from the scheduler.
+    */  
+    void clear()
+    {    
+      while(!m_container.empty())
+      {
+        m_container.pop();
+      }
+    } 
+  };
+
+
+} } // namespace boost::threadpool
+
+
+#endif // THREADPOOL_SCHEDULING_POLICIES_HPP_INCLUDED
+

libs/libcommon/include/common/threadpool/shutdown_policies.hpp

@@ -0,0 +1,83 @@
+/*! \file
+* \brief Shutdown policies.
+*
+* This file contains shutdown policies for thread_pool. 
+* A shutdown policy controls the pool's behavior from the time
+* when the pool is not referenced any longer.
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_SHUTDOWN_POLICIES_HPP_INCLUDED
+#define THREADPOOL_SHUTDOWN_POLICIES_HPP_INCLUDED
+
+
+
+/// The namespace threadpool contains a thread pool and related utility classes.
+namespace boost { namespace threadpool
+{
+
+
+/*! \brief ShutdownPolicy which waits for the completion of all tasks 
+  *          and the worker termination afterwards.
+    *
+  * \param Pool The pool's core type.
+  */ 
+  template<typename Pool>
+  class wait_for_all_tasks
+  {
+  public:
+    static void shutdown(Pool& pool)
+    {
+      pool.wait();
+      pool.terminate_all_workers(true);
+    }
+  };
+
+
+  /*! \brief ShutdownPolicy which waits for the completion of all active tasks 
+  *          and the worker termination afterwards.
+  *
+  * \param Pool The pool's core type.
+  */ 
+  template<typename Pool>
+  class wait_for_active_tasks
+  {
+  public:
+    static void shutdown(Pool& pool)
+    {
+      pool.clear();
+      pool.wait();
+      pool.terminate_all_workers(true);
+    }
+  };
+
+
+  /*! \brief ShutdownPolicy which does not wait for any tasks or worker termination.
+  *
+  * This policy does not wait for any tasks. Nevertheless all active tasks will be processed completely.
+  *
+  * \param Pool The pool's core type.
+  */ 
+  template<typename Pool>
+  class immediately
+  {
+  public:
+    static void shutdown(Pool& pool)
+    {
+      pool.clear();
+      pool.terminate_all_workers(false);
+    }
+  };
+
+} } // namespace boost::threadpool
+
+#endif // THREADPOOL_SHUTDOWN_POLICIES_HPP_INCLUDED

libs/libcommon/include/common/threadpool/size_policies.hpp

@@ -0,0 +1,99 @@
+/*! \file
+* \brief Size policies.
+*
+* This file contains size policies for thread_pool. A size 
+* policy controls the number of worker threads in the pool.
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_SIZE_POLICIES_HPP_INCLUDED
+#define THREADPOOL_SIZE_POLICIES_HPP_INCLUDED
+
+
+
+/// The namespace threadpool contains a thread pool and related utility classes.
+namespace boost { namespace threadpool
+{
+
+  /*! \brief SizePolicyController which provides no functionality.
+  *
+  * \param Pool The pool's core type.
+  */ 
+  template<typename Pool>
+  struct empty_controller
+  {
+    empty_controller(typename Pool::size_policy_type&, shared_ptr<Pool>) {}
+  };
+
+
+  /*! \brief SizePolicyController which allows resizing.
+  *
+  * \param Pool The pool's core type.
+  */ 
+  template< typename Pool >
+  class resize_controller
+  {
+    typedef typename Pool::size_policy_type size_policy_type;
+    reference_wrapper<size_policy_type> m_policy;
+    shared_ptr<Pool> m_pool;                           //!< to make sure that the pool is alive (the policy pointer is valid) as long as the controller exists
+
+  public:
+    resize_controller(size_policy_type& policy, shared_ptr<Pool> pool)
+      : m_policy(policy)
+      , m_pool(pool)
+    {
+    }
+
+    bool resize(size_t worker_count)
+    {
+      return m_policy.get().resize(worker_count);
+    }
+  };
+
+
+  /*! \brief SizePolicy which preserves the thread count.
+  *
+  * \param Pool The pool's core type.
+  */ 
+  template<typename Pool>
+  class static_size
+  {
+    reference_wrapper<Pool volatile> m_pool;
+
+  public:
+    static void init(Pool& pool, size_t const worker_count)
+    {
+      pool.resize(worker_count);
+    }
+
+    static_size(Pool volatile & pool)
+      : m_pool(pool)
+    {}
+
+    bool resize(size_t const worker_count)
+    {
+      return m_pool.get().resize(worker_count);
+    }
+
+    void worker_died_unexpectedly(size_t const new_worker_count)
+    {
+      m_pool.get().resize(new_worker_count + 1);
+    }
+
+    // TODO this functions are not called yet
+    void task_scheduled() {}
+    void task_finished() {}
+  };
+
+} } // namespace boost::threadpool
+
+#endif // THREADPOOL_SIZE_POLICIES_HPP_INCLUDED

libs/libcommon/include/common/threadpool/task_adaptors.hpp

@@ -0,0 +1,176 @@
+/*! \file
+* \brief Task adaptors.
+*
+* This file contains adaptors for task function objects.
+*
+* Copyright (c) 2005-2007 Philipp Henkel
+*
+* Use, modification, and distribution are  subject to the
+* Boost Software License, Version 1.0. (See accompanying  file
+* LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+*
+* http://threadpool.sourceforge.net
+*
+*/
+
+
+#ifndef THREADPOOL_TASK_ADAPTERS_HPP_INCLUDED
+#define THREADPOOL_TASK_ADAPTERS_HPP_INCLUDED
+
+#include <boost/version.hpp>
+
+#if BOOST_VERSION >= 105000
+	#ifndef TIME_UTC
+		#define TIME_UTC TIME_UTC_
+	#endif
+#endif
+
+
+#include <boost/smart_ptr.hpp>
+#include <boost/function.hpp>
+#include <boost/thread.hpp>
+
+
+namespace boost { namespace threadpool
+{
+
+  /*! \brief Standard task function object.
+  *
+  * This function object wraps a nullary function which returns void.
+  * The wrapped function is invoked by calling the operator ().
+  *
+  * \see boost function library
+  *
+  */ 
+  typedef function0<void> task_func;
+
+
+
+
+  /*! \brief Prioritized task function object. 
+  *
+  * This function object wraps a task_func object and binds a priority to it.
+  * prio_task_funcs can be compared using the operator < which realises a partial ordering.
+  * The wrapped task function is invoked by calling the operator ().
+  *
+  * \see prio_scheduler
+  *
+  */ 
+  class prio_task_func
+  {
+  private:
+    unsigned int m_priority;  //!< The priority of the task's function.
+    task_func m_function;     //!< The task's function.
+
+  public:
+    typedef void result_type; //!< Indicates the functor's result type.
+
+  public:
+    /*! Constructor.
+    * \param priority The priority of the task.
+    * \param function The task's function object.
+    */
+    prio_task_func(unsigned int const priority, task_func const & function)
+      : m_priority(priority)
+      , m_function(function)
+    {
+    }
+
+    /*! Executes the task function.
+    */
+    void operator() (void) const
+    {
+      if(m_function)
+      {
+        m_function();
+      }
+    }
+
+    /*! Comparison operator which realises a partial ordering based on priorities.
+    * \param rhs The object to compare with.
+    * \return true if the priority of *this is less than right hand side's priority, false otherwise.
+    */
+    bool operator< (const prio_task_func& rhs) const
+    {
+      return m_priority < rhs.m_priority; 
+    }
+
+  };  // prio_task_func
+
+
+
+ 
+
+
+
+
+  /*! \brief Looped task function object. 
+  *
+  * This function object wraps a boolean thread function object.
+  * The wrapped task function is invoked by calling the operator () and it is executed in regular 
+  * time intervals until false is returned. The interval length may be zero.
+  * Please note that a pool's thread is engaged as long as the task is looped.
+  *
+  */ 
+  class looped_task_func
+  {
+  private:
+    function0<bool> m_function;   //!< The task's function.
+    unsigned int m_break_s;              //!< Duration of breaks in seconds.
+    unsigned int m_break_ns;             //!< Duration of breaks in nano seconds.
+
+  public:
+    typedef void result_type; //!< Indicates the functor's result type.
+
+  public:
+    /*! Constructor.
+    * \param function The task's function object which is looped until false is returned.
+    * \param interval The minimum break time in milli seconds before the first execution of the task function and between the following ones.
+    */
+    looped_task_func(function0<bool> const & function, unsigned int const interval = 0)
+      : m_function(function)
+    {
+      m_break_s  = interval / 1000;
+      m_break_ns = (interval - m_break_s * 1000) * 1000 * 1000;
+    }
+
+    /*! Executes the task function.
+    */
+    void operator() (void) const
+    {
+      if(m_function)
+      {
+        if(m_break_s > 0 || m_break_ns > 0)
+        { // Sleep some time before first execution
+          xtime xt;
+          xtime_get(&xt, TIME_UTC);
+          xt.nsec += m_break_ns;
+          xt.sec += m_break_s;
+          thread::sleep(xt); 
+        }
+
+        while(m_function())
+        {
+          if(m_break_s > 0 || m_break_ns > 0)
+          {
+            xtime xt;
+            xtime_get(&xt, TIME_UTC);
+            xt.nsec += m_break_ns;
+            xt.sec += m_break_s;
+            thread::sleep(xt); 
+          }
+          else
+          {
+            thread::yield(); // Be fair to other threads
+          }
+        }
+      }
+    }
+
+  }; // looped_task_func
+
+
+} } // namespace boost::threadpool
+
+#endif // THREADPOOL_TASK_ADAPTERS_HPP_INCLUDED
+

libs/libcommon/src/tests/multi_version.cpp

@@ -1,6 +1,6 @@
 #include <string.h>
 #include <iostream>
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 #include <functional>
 #include <common/MultiVersion.h>
 

utils/iotest/iotest.cpp

@@ -14,7 +14,7 @@
 
 #include <DB/Core/Exception.h>
 
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 #include <DB/Common/Stopwatch.h>
 
 #include <stdlib.h>

utils/iotest/iotest_aio.cpp

@@ -14,7 +14,7 @@
 
 #include <DB/Core/Exception.h>
 
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 #include <DB/Common/Stopwatch.h>
 
 #include <stdlib.h>

utils/iotest/iotest_nonblock.cpp

@@ -17,7 +17,7 @@
 
 #include <DB/Core/Exception.h>
 
-#include <statdaemons/threadpool.hpp>
+#include <common/threadpool.hpp>
 #include <DB/Common/Stopwatch.h>