private void OnThreadPoolThreadExit(ThreadPoolThread exitedThread)
{
lock (_sync) {
if (_idleThreads.Count <= _minThreadCount)
{
return;
}
Stack <ThreadPoolThread> threads = new Stack <ThreadPoolThread>();
while (_idleThreads.Count != 0)
{
ThreadPoolThread thread = _idleThreads.Pop();
if (thread == exitedThread)
{
if (!_semaphore.WaitOne(0))
{
throw new Exception("Semaphore count is invalid.");
}
break;
}
threads.Push(thread);
}
while (threads.Count != 0)
{
_idleThreads.Push(threads.Pop());
}
}
}
/// <summary>
/// This puts a work request on the queue to be executed. The logic then immediatly tries to assign a thread the work.
/// </summary>
/// <param name="work"></param>
public void AssignThread(Action work)
{
ThreadPoolThread thread = null;
Action currentWork = null;
lock (_lock)
{
if (IsDisposed)
{
return;
}
_workQueue.Enqueue(work);
Interlocked.Increment(ref _workQueueSize);
if (_availableThreads.Count == 0)
{
return;
}
// okay have thread and have work
thread = _availableThreads.Dequeue();
Interlocked.Increment(ref _threadsAssigned);
currentWork = _workQueue.Dequeue(); // this seems strange to deque right after an enqueue but there could be work waiting on the work queue
Interlocked.Decrement(ref _workQueueSize);
}
// we do it here -- the thread and must not be null and should not according to the above logic
thread.AssignWork(currentWork);
}
/// <summary>
/// Creates a ThreadPoolThread instance.
/// </summary>
/// <param name="id">The id for the thread.</param>
/// <returns>The created thread</returns>
private ThreadPoolThread BuildThread(int id)
{
ThreadPoolThread thread = new ThreadPoolThread(_poolName, id + 1, ThreadStarting);
thread.OnFinished += WorkFinished;
return(thread);
}
/// <summary> Puts the thread 't' in the idle list. The thread 't' should be in fact
/// idle and ready to accept a new target when it joins the idle list.
///
/// <P> An idle thread that is already in the list should never add itself
/// to the list before it is removed. For efficiency reasons there is no
/// check to see if the thread is already in the list of idle threads.
///
/// <P> If the idle list was empty 'notify()' will be called on the 'idle'
/// array, to wake up a thread that might be waiting (within the
/// 'getIdle()' method) on an idle thread to become available.
///
/// </summary>
/// <param name="t">The thread to put in the idle list.
///
/// </param>
private void putInIdleList(ThreadPoolThread t)
{
// NOTE: if already in idle => catastrophe! (should be OK since //
// this is private method)
// Lock the idle array to avoid races with 'getIdle()'
lock (idle)
{
idle[nidle] = t;
nidle++;
// If idle array was empty wakeup any waiting threads.
if (nidle == 1)
{
System.Threading.Monitor.Pulse(idle);
}
}
}
/// <summary>
/// Fires the OnNewThreadPoolThread event.
/// </summary>
/// <param name="thread"></param>
private void ThreadStarting(ThreadPoolThread thread)
{
if (null != OnNewThreadPoolThread)
{
try
{
OnNewThreadPoolThread(this, new NewThreadPoolThreadArgs()
{
name = thread.Name,
thread = thread.Thread
});
}
catch (Exception)
{
throw;
}
}
}
/// <summary> Creates a new thread pool of the given size, thread priority and pool
/// name.
///
/// <P>If the Java system property of the name defined by
/// 'CONCURRENCY_PROP_NAME' is set, then an attempt will be made to load
/// the library that supports concurrency setting (see
/// 'NativeServices'). If that succeds the concurrency level will be set to
/// the specified value. Otherwise a warning is printed.
///
/// </summary>
/// <param name="size">The size of the pool (number of threads to create in the
/// pool).
///
/// </param>
/// <param name="priority">The priority to give to the threads in the pool. If
/// less than 'Thread.MIN_PRIORITY' it will be the same as the priority of
/// the calling thread.
///
/// </param>
/// <param name="name">The name of the pool. If null a default generic name is
/// chosen.
///
/// </param>
/// <seealso cref="NativeServices">
///
/// </seealso>
/// <seealso cref="CONCURRENCY_PROP_NAME">
///
/// </seealso>
public ThreadPool(int size, int priority, System.String name)
{
int i;
ThreadPoolThread t;
//System.String prop;
//int clevel;
// Initialize variables checking for special cases
if (size <= 0)
{
throw new System.ArgumentException("Pool must be of positive size");
}
if (priority < (int)System.Threading.ThreadPriority.Lowest)
{
poolPriority = (System.Int32)SupportClass.ThreadClass.Current().Priority;
}
else
{
poolPriority = (priority < (int)System.Threading.ThreadPriority.Highest)?priority:(int)System.Threading.ThreadPriority.Highest;
}
if (name == null)
{
poolName = "Anonymous ThreadPool";
}
else
{
poolName = name;
}
// Allocate internal variables
idle = new ThreadPoolThread[size];
nidle = 0;
// Create and start the threads
for (i = 0; i < size; i++)
{
t = new ThreadPoolThread(this, i, poolName + "-" + i);
t.Start();
}
}
/// <summary>
/// Kills the assigned work off that is in a thread.
/// </summary>
/// <param name="work"></param>
public void KillThread(Action work)
{
ThreadPoolThread t = null;
lock (_lock)
{
int cnt = _allThreads.Length;
for (int i = 0; i < cnt; i++)
{
t = _allThreads[i];
if (t.Work == work)
{
goto kill_it;
}
}
return;
}
kill_it:
t.KillWork();
}
/// <summary>
/// This is called by the ThreadPoolThread when it's finished processing the unit of work it was given.
/// </summary>
/// <param name="thread">The thread that finished</param>
private void WorkFinished(ThreadPoolThread thread)
{
if (IsDisposed)
{
return;
}
Action currentWork = null;
lock (_lock)
{
if (_workQueue.Count > 0)
{
currentWork = _workQueue.Dequeue();
Interlocked.Decrement(ref _workQueueSize);
}
else
{
_availableThreads.Enqueue(thread);
Interlocked.Decrement(ref _threadsAssigned);
}
}
if (null != currentWork)
{
thread.AssignWork(currentWork);
}
if (null != OnThreadFinished)
{
try
{
OnThreadFinished(this, new EventArgs());
}
catch (Exception)
{ }
}
}
public void QueueWorkItem(Action action)
{
_schedulerThread.QueueWorkItem(() => {
ThreadPoolThread thread;
if (_semaphore.WaitOne(_threadCreationDelay))
{
lock (_sync) {
thread = _idleThreads.Pop();
}
}
else
{
thread = new ThreadPoolThread(this);
}
thread.QueueWorkItem(action);
thread.QueueWorkItem(() => {
lock (_sync) {
_idleThreads.Push(thread);
_semaphore.Release();
}
});
});
}
/// <summary> Puts the thread 't' in the idle list. The thread 't' should be in fact
/// idle and ready to accept a new target when it joins the idle list.
///
/// <P> An idle thread that is already in the list should never add itself
/// to the list before it is removed. For efficiency reasons there is no
/// check to see if the thread is already in the list of idle threads.
///
/// <P> If the idle list was empty 'notify()' will be called on the 'idle'
/// array, to wake up a thread that might be waiting (within the
/// 'getIdle()' method) on an idle thread to become available.
///
/// </summary>
/// <param name="t">The thread to put in the idle list.
///
/// </param>
private void putInIdleList(ThreadPoolThread t)
{
// NOTE: if already in idle => catastrophe! (should be OK since //
// this is private method)
// Lock the idle array to avoid races with 'getIdle()'
lock (idle)
{
idle[nidle] = t;
nidle++;
// If idle array was empty wakeup any waiting threads.
if (nidle == 1)
System.Threading.Monitor.Pulse(idle);
}
}
/// <summary> Creates a new thread pool of the given size, thread priority and pool
/// name.
///
/// <P>If the Java system property of the name defined by
/// 'CONCURRENCY_PROP_NAME' is set, then an attempt will be made to load
/// the library that supports concurrency setting (see
/// 'NativeServices'). If that succeds the concurrency level will be set to
/// the specified value. Otherwise a warning is printed.
///
/// </summary>
/// <param name="size">The size of the pool (number of threads to create in the
/// pool).
///
/// </param>
/// <param name="priority">The priority to give to the threads in the pool. If
/// less than 'Thread.MIN_PRIORITY' it will be the same as the priority of
/// the calling thread.
///
/// </param>
/// <param name="name">The name of the pool. If null a default generic name is
/// chosen.
///
/// </param>
/// <seealso cref="NativeServices">
///
/// </seealso>
/// <seealso cref="CONCURRENCY_PROP_NAME">
///
/// </seealso>
public ThreadPool(int size, int priority, System.String name)
{
int i;
ThreadPoolThread t;
//System.String prop;
//int clevel;
// Initialize variables checking for special cases
if (size <= 0)
{
throw new System.ArgumentException("Pool must be of positive size");
}
if (priority < (int) System.Threading.ThreadPriority.Lowest)
{
poolPriority = (System.Int32) SupportClass.ThreadClass.Current().Priority;
}
else
{
poolPriority = (priority < (int) System.Threading.ThreadPriority.Highest)?priority:(int) System.Threading.ThreadPriority.Highest;
}
if (name == null)
{
poolName = "Anonymous ThreadPool";
}
else
{
poolName = name;
}
// Allocate internal variables
idle = new ThreadPoolThread[size];
nidle = 0;
// Create and start the threads
for (i = 0; i < size; i++)
{
t = new ThreadPoolThread(this, i, poolName + "-" + i);
t.Start();
}
}
