icinga2/lib/base/threadpool.hpp

137 lines
3.3 KiB
C++

/******************************************************************************
* Icinga 2 *
* Copyright (C) 2012-2014 Icinga Development Team (http://www.icinga.org) *
* *
* This program is free software; you can redistribute it and/or *
* modify it under the terms of the GNU General Public License *
* as published by the Free Software Foundation; either version 2 *
* of the License, or (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the Free Software Foundation *
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. *
******************************************************************************/
#ifndef THREADPOOL_H
#define THREADPOOL_H
#include "base/i2-base.hpp"
#include <boost/function.hpp>
#include <boost/thread/thread.hpp>
#include <boost/thread/mutex.hpp>
#include <boost/thread/condition_variable.hpp>
#include <deque>
namespace icinga
{
#define QUEUECOUNT 4
enum SchedulerPolicy
{
DefaultScheduler,
LowLatencyScheduler
};
/**
* A thread pool.
*
* @ingroup base
*/
class I2_BASE_API ThreadPool
{
public:
typedef boost::function<void ()> WorkFunction;
ThreadPool(size_t max_threads = UINT_MAX);
~ThreadPool(void);
void Start(void);
void Stop(void);
void Join(bool wait_for_stop = false);
bool Post(const WorkFunction& callback, SchedulerPolicy policy = DefaultScheduler);
private:
enum ThreadState
{
ThreadUnspecified,
ThreadDead,
ThreadIdle,
ThreadBusy
};
struct WorkItem
{
WorkFunction Callback;
double Timestamp;
};
struct Queue;
struct WorkerThread
{
ThreadState State;
bool Zombie;
double Utilization;
double LastUpdate;
boost::thread *Thread;
WorkerThread(ThreadState state = ThreadDead)
: State(state), Zombie(false), Utilization(0), LastUpdate(0), Thread(NULL)
{ }
void UpdateUtilization(ThreadState state = ThreadUnspecified);
void ThreadProc(Queue& queue);
};
struct Queue
{
boost::mutex Mutex;
boost::condition_variable CV;
boost::condition_variable CVStarved;
std::deque<WorkItem> Items;
double WaitTime;
double ServiceTime;
int TaskCount;
bool Stopped;
WorkerThread Threads[16];
Queue(void)
: WaitTime(0), ServiceTime(0), TaskCount(0), Stopped(false)
{ }
void SpawnWorker(boost::thread_group& group);
void KillWorker(boost::thread_group& group);
};
int m_ID;
static int m_NextID;
size_t m_MaxThreads;
boost::thread_group m_ThreadGroup;
boost::mutex m_MgmtMutex;
boost::condition_variable m_MgmtCV;
bool m_Stopped;
Queue m_Queues[QUEUECOUNT];
void ManagerThreadProc(void);
};
}
#endif /* EVENTQUEUE_H */