/// <summary>
/// The worker object for the thread pool
/// </summary>
/// <param name="state"></param>
private void ThreadWorker(object state)
{
WorkerInfo threadInfo = (WorkerInfo)state;
do
{
//While there are jobs in the queue process the jobs
while (true)
{
if (threadInfo.CurrentCallBackWrapper == null)
{
KeyValuePair <QueueItemPriority, WaitCallBackWrapper> packetQueueItem;
lock (SyncRoot)
{
UpdateThreadWaitSleepJoinCountCache();
int numInJobActiveThreadsCount = Math.Max(0, threadDict.Count - CurrentNumWaitSleepJoinThreadsCache - requireJobThreadsCount);
if (shutdown || threadDict.Count > MaxTotalThreadsCount) //If we have too many active threads
{
//If shutdown was true then we may need to set thread to idle
if (threadInfo.ThreadIdle && requireJobThreadsCount > 0)
{
requireJobThreadsCount--;
}
threadInfo.ClearThreadIdle();
threadDict.Remove(threadInfo.ThreadId);
workerInfoDict.Remove(threadInfo.ThreadId);
UpdateThreadWaitSleepJoinCountCache();
return;
}
else if (numInJobActiveThreadsCount > MaxActiveThreadsCount) //If we have too many active threads
{
//We wont close here to prevent thread creation/destruction thrashing.
//We will instead act as if there is no work and wait to potentially be timed out
if (!threadInfo.ThreadIdle)
{
threadInfo.SetThreadIdle();
requireJobThreadsCount++;
}
break;
}
else
{
//Try to get a job
if (!jobQueue.TryTake(out packetQueueItem)) //We fail to get a new job
{
//If we failed to get a job we switch to idle and wait to be triggered
if (!threadInfo.ThreadIdle)
{
threadInfo.SetThreadIdle();
requireJobThreadsCount++;
}
break;
}
else
{
if (threadInfo.ThreadIdle && requireJobThreadsCount > 0)
{
requireJobThreadsCount--;
}
threadInfo.UpdateCurrentCallBackWrapper(packetQueueItem.Value);
threadInfo.ClearThreadIdle();
}
}
}
}
//Perform the waitcallBack
try
{
threadInfo.SetInsideCallBack();
threadInfo.CurrentCallBackWrapper.WaitCallBack(threadInfo.CurrentCallBackWrapper.State);
}
catch (Exception ex)
{
NetworkComms.LogError(ex, "ManagedThreadPoolCallBackError", "An unhandled exception was caught while processing a callback. Make sure to catch errors in callbacks to prevent this error file being produced.");
}
finally
{
threadInfo.ClearInsideCallBack();
}
threadInfo.UpdateLastActiveTime();
threadInfo.ClearCallBackWrapper();
}
//As soon as the queue is empty we wait until perhaps close time
if (!threadInfo.ThreadSignal.WaitOne(250))
{
//While we are waiting we check to see if we need to close
if (DateTime.Now - threadInfo.LastActiveTime > ThreadIdleTimeoutClose)
{
lock (SyncRoot)
{
//We have timed out but we don't go below the minimum
if (threadDict.Count > MinThreadsCount)
{
if (threadInfo.ThreadIdle && requireJobThreadsCount > 0)
{
requireJobThreadsCount--;
}
threadInfo.ClearThreadIdle();
threadDict.Remove(threadInfo.ThreadId);
workerInfoDict.Remove(threadInfo.ThreadId);
UpdateThreadWaitSleepJoinCountCache();
return;
}
}
}
}
//We only leave via one of our possible breaks
} while (true);
}
/// <summary>
/// Enqueue a callback to the thread pool.
/// </summary>
/// <param name="priority">The priority with which to enqueue the provided callback</param>
/// <param name="callback">The callback to execute</param>
/// <param name="state">The state parameter to pass to the callback when executed</param>
/// <returns>Returns the managed threadId running the callback if one was available, otherwise -1</returns>
public int EnqueueItem(QueueItemPriority priority, WaitCallback callback, object state)
{
int chosenThreadId = -1;
lock (SyncRoot)
{
UpdateThreadWaitSleepJoinCountCache();
int numInJobActiveThreadsCount = Math.Max(0, threadDict.Count - CurrentNumWaitSleepJoinThreadsCache - requireJobThreadsCount);
//int numActiveThreads = Math.Max(0,threadDict.Count - CurrentNumWaitSleepJoinThreadsCache);
if (!shutdown && requireJobThreadsCount == 0 && numInJobActiveThreadsCount < MaxActiveThreadsCount && threadDict.Count < MaxTotalThreadsCount)
{
//Launch a new thread
Thread newThread = new Thread(ThreadWorker);
newThread.Name = "ManagedThreadPool_" + newThread.ManagedThreadId.ToString();
WorkerInfo info = new WorkerInfo(newThread.ManagedThreadId, new WaitCallBackWrapper(callback, state));
chosenThreadId = newThread.ManagedThreadId;
threadDict.Add(newThread.ManagedThreadId, newThread);
workerInfoDict.Add(newThread.ManagedThreadId, info);
newThread.Start(info);
}
else if (!shutdown && requireJobThreadsCount > 0 && numInJobActiveThreadsCount < MaxActiveThreadsCount)
{
jobQueue.TryAdd(new KeyValuePair <QueueItemPriority, WaitCallBackWrapper>(priority, new WaitCallBackWrapper(callback, state)));
int checkCount = 0;
foreach (var info in workerInfoDict)
{
//Trigger the first idle thread
checkCount++;
if (info.Value.ThreadIdle)
{
info.Value.ClearThreadIdle();
requireJobThreadsCount--;
info.Value.ThreadSignal.Set();
chosenThreadId = info.Value.ThreadId;
break;
}
if (checkCount == workerInfoDict.Count)
{
throw new Exception("IdleThreads count is " + requireJobThreadsCount.ToString() + " but unable to locate thread marked as idle.");
}
}
}
else if (!shutdown)
{
//If there are no idle threads and we can't start any new ones we just have to enqueue the item
jobQueue.TryAdd(new KeyValuePair <QueueItemPriority, WaitCallBackWrapper>(priority, new WaitCallBackWrapper(callback, state)));
}
}
return(chosenThreadId);
}
