OpenSimMirror/ThirdParty/SmartThreadPool/SmartThreadPool.cs

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C#
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#region Release History
// Smart Thread Pool
// 7 Aug 2004 - Initial release
//
// 14 Sep 2004 - Bug fixes
//
// 15 Oct 2004 - Added new features
// - Work items return result.
// - Support waiting synchronization for multiple work items.
// - Work items can be cancelled.
// - Passage of the caller threads context to the thread in the pool.
// - Minimal usage of WIN32 handles.
// - Minor bug fixes.
//
// 26 Dec 2004 - Changes:
// - Removed static constructors.
// - Added finalizers.
// - Changed Exceptions so they are serializable.
// - Fixed the bug in one of the SmartThreadPool constructors.
// - Changed the SmartThreadPool.WaitAll() so it will support any number of waiters.
// The SmartThreadPool.WaitAny() is still limited by the .NET Framework.
// - Added PostExecute with options on which cases to call it.
// - Added option to dispose of the state objects.
// - Added a WaitForIdle() method that waits until the work items queue is empty.
// - Added an STPStartInfo class for the initialization of the thread pool.
// - Changed exception handling so if a work item throws an exception it
// is rethrown at GetResult(), rather then firing an UnhandledException event.
// Note that PostExecute exception are always ignored.
//
// 25 Mar 2005 - Changes:
// - Fixed lost of work items bug
//
// 3 Jul 2005: Changes.
// - Fixed bug where Enqueue() throws an exception because PopWaiter() returned null, hardly reconstructed.
//
// 16 Aug 2005: Changes.
// - Fixed bug where the InUseThreads becomes negative when canceling work items.
//
// 31 Jan 2006 - Changes:
// - Added work items priority
// - Removed support of chained delegates in callbacks and post executes (nobody really use this)
// - Added work items groups
// - Added work items groups idle event
// - Changed SmartThreadPool.WaitAll() behavior so when it gets empty array
// it returns true rather then throwing an exception.
// - Added option to start the STP and the WIG as suspended
// - Exception behavior changed, the real exception is returned by an
// inner exception
// - Added option to keep the Http context of the caller thread. (Thanks to Steven T.)
// - Added performance counters
// - Added priority to the threads in the pool
//
// 13 Feb 2006 - Changes:
// - Added a call to the dispose of the Performance Counter so
// their won't be a Performance Counter leak.
// - Added exception catch in case the Performance Counters cannot
// be created.
//
// 17 May 2008 - Changes:
// - Changed the dispose behavior and removed the Finalizers.
// - Enabled the change of the MaxThreads and MinThreads at run time.
// - Enabled the change of the Concurrency of a IWorkItemsGroup at run
// time If the IWorkItemsGroup is a SmartThreadPool then the Concurrency
// refers to the MaxThreads.
// - Improved the cancel behavior.
// - Added events for thread creation and termination.
// - Fixed the HttpContext context capture.
// - Changed internal collections so they use generic collections
// - Added IsIdle flag to the SmartThreadPool and IWorkItemsGroup
// - Added support for WinCE
// - Added support for Action<T> and Func<T>
//
// 07 April 2009 - Changes:
// - Added support for Silverlight and Mono
// - Added Join, Choice, and Pipe to SmartThreadPool.
// - Added local performance counters (for Mono, Silverlight, and WindowsCE)
// - Changed duration measures from DateTime.Now to Stopwatch.
// - Queues changed from System.Collections.Queue to System.Collections.Generic.LinkedList<T>.
//
// 21 December 2009 - Changes:
// - Added work item timeout (passive)
//
// 20 August 2012 - Changes:
// - Added set name to threads
// - Fixed the WorkItemsQueue.Dequeue.
// Replaced while (!Monitor.TryEnter(this)); with lock(this) { ... }
// - Fixed SmartThreadPool.Pipe
// - Added IsBackground option to threads
// - Added ApartmentState to threads
// - Fixed thread creation when queuing many work items at the same time.
//
// 24 August 2012 - Changes:
// - Enabled cancel abort after cancel. See: http://smartthreadpool.codeplex.com/discussions/345937 by alecswan
// - Added option to set MaxStackSize of threads
#endregion
using System;
using System.Security;
using System.Threading;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Runtime.CompilerServices;
using Amib.Threading.Internal;
namespace Amib.Threading
{
#region SmartThreadPool class
/// <summary>
/// Smart thread pool class.
/// </summary>
public partial class SmartThreadPool : WorkItemsGroupBase, IDisposable
{
#region Public Default Constants
/// <summary>
/// Default minimum number of threads the thread pool contains. (0)
/// </summary>
public const int DefaultMinWorkerThreads = 0;
/// <summary>
/// Default maximum number of threads the thread pool contains. (25)
/// </summary>
public const int DefaultMaxWorkerThreads = 25;
/// <summary>
/// Default idle timeout in milliseconds. (One minute)
/// </summary>
public const int DefaultIdleTimeout = 60*1000; // One minute
/// <summary>
/// Indicate to copy the security context of the caller and then use it in the call. (false)
/// </summary>
public const bool DefaultUseCallerCallContext = false;
/// <summary>
/// Indicate to copy the HTTP context of the caller and then use it in the call. (false)
/// </summary>
public const bool DefaultUseCallerHttpContext = false;
/// <summary>
/// Indicate to dispose of the state objects if they support the IDispose interface. (false)
/// </summary>
public const bool DefaultDisposeOfStateObjects = false;
/// <summary>
/// The default option to run the post execute (CallToPostExecute.Always)
/// </summary>
public const CallToPostExecute DefaultCallToPostExecute = CallToPostExecute.Always;
/// <summary>
/// The default post execute method to run. (None)
/// When null it means not to call it.
/// </summary>
public static readonly PostExecuteWorkItemCallback DefaultPostExecuteWorkItemCallback;
/// <summary>
/// The default work item priority (WorkItemPriority.Normal)
/// </summary>
public const WorkItemPriority DefaultWorkItemPriority = WorkItemPriority.Normal;
/// <summary>
/// The default is to work on work items as soon as they arrive
/// and not to wait for the start. (false)
/// </summary>
public const bool DefaultStartSuspended = false;
/// <summary>
/// The default name to use for the performance counters instance. (null)
/// </summary>
public static readonly string DefaultPerformanceCounterInstanceName;
#if !(WINDOWS_PHONE)
/// <summary>
/// The default thread priority (ThreadPriority.Normal)
/// </summary>
public const ThreadPriority DefaultThreadPriority = ThreadPriority.Normal;
#endif
/// <summary>
/// The default thread pool name. (SmartThreadPool)
/// </summary>
public const string DefaultThreadPoolName = "SmartThreadPool";
/// <summary>
/// The default Max Stack Size. (SmartThreadPool)
/// </summary>
public static readonly int? DefaultMaxStackSize = null;
/// <summary>
/// The default fill state with params. (false)
/// It is relevant only to QueueWorkItem of Action&lt;...&gt;/Func&lt;...&gt;
/// </summary>
public const bool DefaultFillStateWithArgs = false;
/// <summary>
/// The default thread backgroundness. (true)
/// </summary>
public const bool DefaultAreThreadsBackground = true;
#if !(_SILVERLIGHT) && !(WINDOWS_PHONE)
/// <summary>
/// The default apartment state of a thread in the thread pool.
/// The default is ApartmentState.Unknown which means the STP will not
/// set the apartment of the thread. It will use the .NET default.
/// </summary>
public const ApartmentState DefaultApartmentState = ApartmentState.Unknown;
#endif
#endregion
#region Member Variables
/// <summary>
/// Dictionary of all the threads in the thread pool.
/// </summary>
private readonly SynchronizedDictionary<Thread, ThreadEntry> _workerThreads = new SynchronizedDictionary<Thread, ThreadEntry>();
/// <summary>
/// Queue of work items.
/// </summary>
private readonly WorkItemsQueue _workItemsQueue = new WorkItemsQueue();
/// <summary>
/// Count the work items handled.
/// Used by the performance counter.
/// </summary>
private int _workItemsProcessed;
/// <summary>
/// Number of threads that currently work (not idle).
/// </summary>
private int _inUseWorkerThreads;
/// <summary>
/// Stores a copy of the original STPStartInfo.
/// It is used to change the MinThread and MaxThreads
/// </summary>
private STPStartInfo _stpStartInfo;
/// <summary>
/// Total number of work items that are stored in the work items queue
/// plus the work items that the threads in the pool are working on.
/// </summary>
private int _currentWorkItemsCount;
/// <summary>
/// Signaled when the thread pool is idle, i.e. no thread is busy
/// and the work items queue is empty
/// </summary>
//private ManualResetEvent _isIdleWaitHandle = new ManualResetEvent(true);
private ManualResetEvent _isIdleWaitHandle = EventWaitHandleFactory.CreateManualResetEvent(true);
/// <summary>
/// An event to signal all the threads to quit immediately.
/// </summary>
//private ManualResetEvent _shuttingDownEvent = new ManualResetEvent(false);
private ManualResetEvent _shuttingDownEvent = EventWaitHandleFactory.CreateManualResetEvent(false);
/// <summary>
/// A flag to indicate if the Smart Thread Pool is now suspended.
/// </summary>
private bool _isSuspended;
/// <summary>
/// A flag to indicate the threads to quit.
/// </summary>
private bool _shutdown;
/// <summary>
/// Counts the threads created in the pool.
/// It is used to name the threads.
/// </summary>
private int _threadCounter;
/// <summary>
/// Indicate that the SmartThreadPool has been disposed
/// </summary>
private bool _isDisposed;
/// <summary>
/// Holds all the WorkItemsGroup instaces that have at least one
/// work item int the SmartThreadPool
/// This variable is used in case of Shutdown
/// </summary>
private readonly SynchronizedDictionary<IWorkItemsGroup, IWorkItemsGroup> _workItemsGroups = new SynchronizedDictionary<IWorkItemsGroup, IWorkItemsGroup>();
/// <summary>
/// A common object for all the work items int the STP
/// so we can mark them to cancel in O(1)
/// </summary>
private CanceledWorkItemsGroup _canceledSmartThreadPool = new CanceledWorkItemsGroup();
/// <summary>
/// Windows STP performance counters
/// </summary>
private ISTPInstancePerformanceCounters _windowsPCs = NullSTPInstancePerformanceCounters.Instance;
/// <summary>
/// Local STP performance counters
/// </summary>
private ISTPInstancePerformanceCounters _localPCs = NullSTPInstancePerformanceCounters.Instance;
#if (WINDOWS_PHONE)
private static readonly Dictionary<int, ThreadEntry> _threadEntries = new Dictionary<int, ThreadEntry>();
#elif (_WINDOWS_CE)
private static LocalDataStoreSlot _threadEntrySlot = Thread.AllocateDataSlot();
#else
[ThreadStatic]
private static ThreadEntry _threadEntry;
#endif
/// <summary>
/// An event to call after a thread is created, but before
/// it's first use.
/// </summary>
private event ThreadInitializationHandler _onThreadInitialization;
/// <summary>
/// An event to call when a thread is about to exit, after
/// it is no longer belong to the pool.
/// </summary>
private event ThreadTerminationHandler _onThreadTermination;
#endregion
#region Per thread properties
/// <summary>
/// A reference to the current work item a thread from the thread pool
/// is executing.
/// </summary>
internal static ThreadEntry CurrentThreadEntry
{
#if (WINDOWS_PHONE)
get
{
lock(_threadEntries)
{
ThreadEntry threadEntry;
if (_threadEntries.TryGetValue(Thread.CurrentThread.ManagedThreadId, out threadEntry))
{
return threadEntry;
}
}
return null;
}
set
{
lock(_threadEntries)
{
_threadEntries[Thread.CurrentThread.ManagedThreadId] = value;
}
}
#elif (_WINDOWS_CE)
get
{
//Thread.CurrentThread.ManagedThreadId
return Thread.GetData(_threadEntrySlot) as ThreadEntry;
}
set
{
Thread.SetData(_threadEntrySlot, value);
}
#else
get
{
return _threadEntry;
}
set
{
_threadEntry = value;
}
#endif
}
#endregion
#region Construction and Finalization
/// <summary>
/// Constructor
/// </summary>
public SmartThreadPool()
{
_stpStartInfo = new STPStartInfo();
Initialize();
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="idleTimeout">Idle timeout in milliseconds</param>
public SmartThreadPool(int idleTimeout)
{
_stpStartInfo = new STPStartInfo
{
IdleTimeout = idleTimeout,
};
Initialize();
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="idleTimeout">Idle timeout in milliseconds</param>
/// <param name="maxWorkerThreads">Upper limit of threads in the pool</param>
public SmartThreadPool(
int idleTimeout,
int maxWorkerThreads)
{
_stpStartInfo = new STPStartInfo
{
IdleTimeout = idleTimeout,
MaxWorkerThreads = maxWorkerThreads,
};
Initialize();
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="idleTimeout">Idle timeout in milliseconds</param>
/// <param name="maxWorkerThreads">Upper limit of threads in the pool</param>
/// <param name="minWorkerThreads">Lower limit of threads in the pool</param>
public SmartThreadPool(
int idleTimeout,
int maxWorkerThreads,
int minWorkerThreads)
{
_stpStartInfo = new STPStartInfo
{
IdleTimeout = idleTimeout,
MaxWorkerThreads = maxWorkerThreads,
MinWorkerThreads = minWorkerThreads,
};
Initialize();
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="stpStartInfo">A SmartThreadPool configuration that overrides the default behavior</param>
public SmartThreadPool(STPStartInfo stpStartInfo)
{
_stpStartInfo = new STPStartInfo(stpStartInfo);
Initialize();
}
private void Initialize()
{
Name = _stpStartInfo.ThreadPoolName;
ValidateSTPStartInfo();
// _stpStartInfoRW stores a read/write copy of the STPStartInfo.
// Actually only MaxWorkerThreads and MinWorkerThreads are overwritten
_isSuspended = _stpStartInfo.StartSuspended;
#if (_WINDOWS_CE) || (_SILVERLIGHT) || (_MONO) || (WINDOWS_PHONE)
if (null != _stpStartInfo.PerformanceCounterInstanceName)
{
throw new NotSupportedException("Performance counters are not implemented for Compact Framework/Silverlight/Mono, instead use StpStartInfo.EnableLocalPerformanceCounters");
}
#else
if (null != _stpStartInfo.PerformanceCounterInstanceName)
{
try
{
_windowsPCs = new STPInstancePerformanceCounters(_stpStartInfo.PerformanceCounterInstanceName);
}
catch (Exception e)
{
Debug.WriteLine("Unable to create Performance Counters: " + e);
_windowsPCs = NullSTPInstancePerformanceCounters.Instance;
}
}
#endif
if (_stpStartInfo.EnableLocalPerformanceCounters)
{
_localPCs = new LocalSTPInstancePerformanceCounters();
}
// If the STP is not started suspended then start the threads.
if (!_isSuspended)
{
StartOptimalNumberOfThreads();
}
}
private void StartOptimalNumberOfThreads()
{
int threadsCount = Math.Max(_workItemsQueue.Count, _stpStartInfo.MinWorkerThreads);
threadsCount = Math.Min(threadsCount, _stpStartInfo.MaxWorkerThreads);
threadsCount -= _workerThreads.Count;
if (threadsCount > 0)
{
StartThreads(threadsCount);
}
}
private void ValidateSTPStartInfo()
{
if (_stpStartInfo.MinWorkerThreads < 0)
{
throw new ArgumentOutOfRangeException(
"MinWorkerThreads", "MinWorkerThreads cannot be negative");
}
if (_stpStartInfo.MaxWorkerThreads <= 0)
{
throw new ArgumentOutOfRangeException(
"MaxWorkerThreads", "MaxWorkerThreads must be greater than zero");
}
if (_stpStartInfo.MinWorkerThreads > _stpStartInfo.MaxWorkerThreads)
{
throw new ArgumentOutOfRangeException(
"MinWorkerThreads, maxWorkerThreads",
"MaxWorkerThreads must be greater or equal to MinWorkerThreads");
}
}
private static void ValidateCallback(Delegate callback)
{
if(callback.GetInvocationList().Length > 1)
{
throw new NotSupportedException("SmartThreadPool doesn't support delegates chains");
}
}
#endregion
#region Thread Processing
/// <summary>
/// Waits on the queue for a work item, shutdown, or timeout.
/// </summary>
/// <returns>
/// Returns the WaitingCallback or null in case of timeout or shutdown.
/// </returns>
private WorkItem Dequeue()
{
WorkItem workItem =
_workItemsQueue.DequeueWorkItem(_stpStartInfo.IdleTimeout, _shuttingDownEvent);
return workItem;
}
/// <summary>
/// Put a new work item in the queue
/// </summary>
/// <param name="workItem">A work item to queue</param>
internal override void Enqueue(WorkItem workItem)
{
// Make sure the workItem is not null
Debug.Assert(null != workItem);
IncrementWorkItemsCount();
workItem.CanceledSmartThreadPool = _canceledSmartThreadPool;
_workItemsQueue.EnqueueWorkItem(workItem);
workItem.WorkItemIsQueued();
// If all the threads are busy then try to create a new one
if (_currentWorkItemsCount > _workerThreads.Count)
{
StartThreads(1);
}
}
private void IncrementWorkItemsCount()
{
_windowsPCs.SampleWorkItems(_workItemsQueue.Count, _workItemsProcessed);
_localPCs.SampleWorkItems(_workItemsQueue.Count, _workItemsProcessed);
int count = Interlocked.Increment(ref _currentWorkItemsCount);
//Trace.WriteLine("WorkItemsCount = " + _currentWorkItemsCount.ToString());
if (count == 1)
{
IsIdle = false;
_isIdleWaitHandle.Reset();
}
}
private void DecrementWorkItemsCount()
{
int count = Interlocked.Decrement(ref _currentWorkItemsCount);
//Trace.WriteLine("WorkItemsCount = " + _currentWorkItemsCount.ToString());
if (count == 0)
{
IsIdle = true;
_isIdleWaitHandle.Set();
}
Interlocked.Increment(ref _workItemsProcessed);
if (!_shutdown)
{
// The counter counts even if the work item was cancelled
_windowsPCs.SampleWorkItems(_workItemsQueue.Count, _workItemsProcessed);
_localPCs.SampleWorkItems(_workItemsQueue.Count, _workItemsProcessed);
}
}
internal void RegisterWorkItemsGroup(IWorkItemsGroup workItemsGroup)
{
_workItemsGroups[workItemsGroup] = workItemsGroup;
}
internal void UnregisterWorkItemsGroup(IWorkItemsGroup workItemsGroup)
{
if (_workItemsGroups.Contains(workItemsGroup))
{
_workItemsGroups.Remove(workItemsGroup);
}
}
/// <summary>
/// Inform that the current thread is about to quit or quiting.
/// The same thread may call this method more than once.
/// </summary>
private void InformCompleted()
{
// There is no need to lock the two methods together
// since only the current thread removes itself
// and the _workerThreads is a synchronized dictionary
if (_workerThreads.Contains(Thread.CurrentThread))
{
_workerThreads.Remove(Thread.CurrentThread);
_windowsPCs.SampleThreads(_workerThreads.Count, _inUseWorkerThreads);
_localPCs.SampleThreads(_workerThreads.Count, _inUseWorkerThreads);
}
}
/// <summary>
/// Starts new threads
/// </summary>
/// <param name="threadsCount">The number of threads to start</param>
private void StartThreads(int threadsCount)
{
if (_isSuspended)
{
return;
}
lock(_workerThreads.SyncRoot)
{
// Don't start threads on shut down
if (_shutdown)
{
return;
}
for(int i = 0; i < threadsCount; ++i)
{
// Don't create more threads then the upper limit
if (_workerThreads.Count >= _stpStartInfo.MaxWorkerThreads)
{
return;
}
// Create a new thread
#if (_SILVERLIGHT) || (WINDOWS_PHONE)
Thread workerThread = new Thread(ProcessQueuedItems);
#else
Thread workerThread =
_stpStartInfo.MaxStackSize.HasValue
? new Thread(ProcessQueuedItems, _stpStartInfo.MaxStackSize.Value)
: new Thread(ProcessQueuedItems);
#endif
// Configure the new thread and start it
workerThread.IsBackground = _stpStartInfo.AreThreadsBackground;
#if !(_SILVERLIGHT) && !(_WINDOWS_CE) && !(WINDOWS_PHONE)
if (_stpStartInfo.ApartmentState != ApartmentState.Unknown)
{
workerThread.SetApartmentState(_stpStartInfo.ApartmentState);
}
#endif
#if !(_SILVERLIGHT) && !(WINDOWS_PHONE)
workerThread.Priority = _stpStartInfo.ThreadPriority;
#endif
workerThread.Name = string.Format("STP:{0}:{1}", Name, _threadCounter);
workerThread.Start();
++_threadCounter;
// Add it to the dictionary and update its creation time.
_workerThreads[workerThread] = new ThreadEntry(this);
_windowsPCs.SampleThreads(_workerThreads.Count, _inUseWorkerThreads);
_localPCs.SampleThreads(_workerThreads.Count, _inUseWorkerThreads);
}
}
}
/// <summary>
/// A worker thread method that processes work items from the work items queue.
/// </summary>
private void ProcessQueuedItems()
{
// Keep the entry of the dictionary as thread's variable to avoid the synchronization locks
// of the dictionary.
CurrentThreadEntry = _workerThreads[Thread.CurrentThread];
FireOnThreadInitialization();
try
{
bool bInUseWorkerThreadsWasIncremented = false;
// Process until shutdown.
while(!_shutdown)
{
// Update the last time this thread was seen alive.
// It's good for debugging.
CurrentThreadEntry.IAmAlive();
// The following block handles the when the MaxWorkerThreads has been
// incremented by the user at run-time.
// Double lock for quit.
if (_workerThreads.Count > _stpStartInfo.MaxWorkerThreads)
{
lock (_workerThreads.SyncRoot)
{
if (_workerThreads.Count > _stpStartInfo.MaxWorkerThreads)
{
// Inform that the thread is quiting and then quit.
// This method must be called within this lock or else
// more threads will quit and the thread pool will go
// below the lower limit.
InformCompleted();
break;
}
}
}
// Wait for a work item, shutdown, or timeout
WorkItem workItem = Dequeue();
// Update the last time this thread was seen alive.
// It's good for debugging.
CurrentThreadEntry.IAmAlive();
// On timeout or shut down.
if (null == workItem)
{
// Double lock for quit.
if (_workerThreads.Count > _stpStartInfo.MinWorkerThreads)
{
lock(_workerThreads.SyncRoot)
{
if (_workerThreads.Count > _stpStartInfo.MinWorkerThreads)
{
// Inform that the thread is quiting and then quit.
// This method must be called within this lock or else
// more threads will quit and the thread pool will go
// below the lower limit.
InformCompleted();
break;
}
}
}
}
// If we didn't quit then skip to the next iteration.
if (null == workItem)
{
continue;
}
try
{
// Initialize the value to false
bInUseWorkerThreadsWasIncremented = false;
// Set the Current Work Item of the thread.
// Store the Current Work Item before the workItem.StartingWorkItem() is called,
// so WorkItem.Cancel can work when the work item is between InQueue and InProgress
// states.
// If the work item has been cancelled BEFORE the workItem.StartingWorkItem()
// (work item is in InQueue state) then workItem.StartingWorkItem() will return false.
// If the work item has been cancelled AFTER the workItem.StartingWorkItem() then
// (work item is in InProgress state) then the thread will be aborted
CurrentThreadEntry.CurrentWorkItem = workItem;
// Change the state of the work item to 'in progress' if possible.
// We do it here so if the work item has been canceled we won't
// increment the _inUseWorkerThreads.
// The cancel mechanism doesn't delete items from the queue,
// it marks the work item as canceled, and when the work item
// is dequeued, we just skip it.
// If the post execute of work item is set to always or to
// call when the work item is canceled then the StartingWorkItem()
// will return true, so the post execute can run.
if (!workItem.StartingWorkItem())
{
continue;
}
// Execute the callback. Make sure to accurately
// record how many callbacks are currently executing.
int inUseWorkerThreads = Interlocked.Increment(ref _inUseWorkerThreads);
_windowsPCs.SampleThreads(_workerThreads.Count, inUseWorkerThreads);
_localPCs.SampleThreads(_workerThreads.Count, inUseWorkerThreads);
// Mark that the _inUseWorkerThreads incremented, so in the finally{}
// statement we will decrement it correctly.
bInUseWorkerThreadsWasIncremented = true;
workItem.FireWorkItemStarted();
ExecuteWorkItem(workItem);
}
catch(Exception ex)
{
ex.GetHashCode();
// Do nothing
}
finally
{
workItem.DisposeOfState();
// Set the CurrentWorkItem to null, since we
// no longer run user's code.
CurrentThreadEntry.CurrentWorkItem = null;
// Decrement the _inUseWorkerThreads only if we had
// incremented it. Note the cancelled work items don't
// increment _inUseWorkerThreads.
if (bInUseWorkerThreadsWasIncremented)
{
int inUseWorkerThreads = Interlocked.Decrement(ref _inUseWorkerThreads);
_windowsPCs.SampleThreads(_workerThreads.Count, inUseWorkerThreads);
_localPCs.SampleThreads(_workerThreads.Count, inUseWorkerThreads);
}
// Notify that the work item has been completed.
// WorkItemsGroup may enqueue their next work item.
workItem.FireWorkItemCompleted();
// Decrement the number of work items here so the idle
// ManualResetEvent won't fluctuate.
DecrementWorkItemsCount();
}
}
}
catch(ThreadAbortException tae)
{
tae.GetHashCode();
// Handle the abort exception gracfully.
#if !(_WINDOWS_CE) && !(_SILVERLIGHT) && !(WINDOWS_PHONE)
Thread.ResetAbort();
#endif
}
catch(Exception e)
{
Debug.Assert(null != e);
}
finally
{
InformCompleted();
FireOnThreadTermination();
}
}
private void ExecuteWorkItem(WorkItem workItem)
{
_windowsPCs.SampleWorkItemsWaitTime(workItem.WaitingTime);
_localPCs.SampleWorkItemsWaitTime(workItem.WaitingTime);
try
{
workItem.Execute();
}
finally
{
_windowsPCs.SampleWorkItemsProcessTime(workItem.ProcessTime);
_localPCs.SampleWorkItemsProcessTime(workItem.ProcessTime);
}
}
#endregion
#region Public Methods
private void ValidateWaitForIdle()
{
if (null != CurrentThreadEntry && CurrentThreadEntry.AssociatedSmartThreadPool == this)
{
throw new NotSupportedException(
"WaitForIdle cannot be called from a thread on its SmartThreadPool, it causes a deadlock");
}
}
internal static void ValidateWorkItemsGroupWaitForIdle(IWorkItemsGroup workItemsGroup)
{
if (null == CurrentThreadEntry)
{
return;
}
WorkItem workItem = CurrentThreadEntry.CurrentWorkItem;
ValidateWorkItemsGroupWaitForIdleImpl(workItemsGroup, workItem);
if ((null != workItemsGroup) &&
(null != workItem) &&
CurrentThreadEntry.CurrentWorkItem.WasQueuedBy(workItemsGroup))
{
throw new NotSupportedException("WaitForIdle cannot be called from a thread on its SmartThreadPool, it causes a deadlock");
}
}
[MethodImpl(MethodImplOptions.NoInlining)]
private static void ValidateWorkItemsGroupWaitForIdleImpl(IWorkItemsGroup workItemsGroup, WorkItem workItem)
{
if ((null != workItemsGroup) &&
(null != workItem) &&
workItem.WasQueuedBy(workItemsGroup))
{
throw new NotSupportedException("WaitForIdle cannot be called from a thread on its SmartThreadPool, it causes a deadlock");
}
}
/// <summary>
/// Force the SmartThreadPool to shutdown
/// </summary>
public void Shutdown()
{
Shutdown(true, 0);
}
/// <summary>
/// Force the SmartThreadPool to shutdown with timeout
/// </summary>
public void Shutdown(bool forceAbort, TimeSpan timeout)
{
Shutdown(forceAbort, (int)timeout.TotalMilliseconds);
}
/// <summary>
/// Empties the queue of work items and abort the threads in the pool.
/// </summary>
public void Shutdown(bool forceAbort, int millisecondsTimeout)
{
ValidateNotDisposed();
ISTPInstancePerformanceCounters pcs = _windowsPCs;
if (NullSTPInstancePerformanceCounters.Instance != _windowsPCs)
{
// Set the _pcs to "null" to stop updating the performance
// counters
_windowsPCs = NullSTPInstancePerformanceCounters.Instance;
pcs.Dispose();
}
Thread [] threads;
lock(_workerThreads.SyncRoot)
{
// Shutdown the work items queue
_workItemsQueue.Dispose();
// Signal the threads to exit
_shutdown = true;
_shuttingDownEvent.Set();
// Make a copy of the threads' references in the pool
threads = new Thread [_workerThreads.Count];
_workerThreads.Keys.CopyTo(threads, 0);
}
int millisecondsLeft = millisecondsTimeout;
Stopwatch stopwatch = Stopwatch.StartNew();
//DateTime start = DateTime.UtcNow;
bool waitInfinitely = (Timeout.Infinite == millisecondsTimeout);
bool timeout = false;
// Each iteration we update the time left for the timeout.
foreach(Thread thread in threads)
{
// Join don't work with negative numbers
if (!waitInfinitely && (millisecondsLeft < 0))
{
timeout = true;
break;
}
// Wait for the thread to terminate
bool success = thread.Join(millisecondsLeft);
if(!success)
{
timeout = true;
break;
}
if(!waitInfinitely)
{
// Update the time left to wait
//TimeSpan ts = DateTime.UtcNow - start;
millisecondsLeft = millisecondsTimeout - (int)stopwatch.ElapsedMilliseconds;
}
}
if (timeout && forceAbort)
{
// Abort the threads in the pool
foreach(Thread thread in threads)
{
if ((thread != null)
#if !(_WINDOWS_CE)
&& thread.IsAlive
#endif
)
{
try
{
thread.Abort(); // Shutdown
}
catch(SecurityException e)
{
e.GetHashCode();
}
catch(ThreadStateException ex)
{
ex.GetHashCode();
// In case the thread has been terminated
// after the check if it is alive.
}
}
}
}
}
/// <summary>
/// Wait for all work items to complete
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <returns>
/// true when every work item in workItemResults has completed; otherwise false.
/// </returns>
public static bool WaitAll(
IWaitableResult [] waitableResults)
{
return WaitAll(waitableResults, Timeout.Infinite, true);
}
/// <summary>
/// Wait for all work items to complete
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <param name="timeout">The number of milliseconds to wait, or a TimeSpan that represents -1 milliseconds to wait indefinitely. </param>
/// <param name="exitContext">
/// true to exit the synchronization domain for the context before the wait (if in a synchronized context), and reacquire it; otherwise, false.
/// </param>
/// <returns>
/// true when every work item in workItemResults has completed; otherwise false.
/// </returns>
public static bool WaitAll(
IWaitableResult [] waitableResults,
TimeSpan timeout,
bool exitContext)
{
return WaitAll(waitableResults, (int)timeout.TotalMilliseconds, exitContext);
}
/// <summary>
/// Wait for all work items to complete
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <param name="timeout">The number of milliseconds to wait, or a TimeSpan that represents -1 milliseconds to wait indefinitely. </param>
/// <param name="exitContext">
/// true to exit the synchronization domain for the context before the wait (if in a synchronized context), and reacquire it; otherwise, false.
/// </param>
/// <param name="cancelWaitHandle">A cancel wait handle to interrupt the wait if needed</param>
/// <returns>
/// true when every work item in workItemResults has completed; otherwise false.
/// </returns>
public static bool WaitAll(
IWaitableResult[] waitableResults,
TimeSpan timeout,
bool exitContext,
WaitHandle cancelWaitHandle)
{
return WaitAll(waitableResults, (int)timeout.TotalMilliseconds, exitContext, cancelWaitHandle);
}
/// <summary>
/// Wait for all work items to complete
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <param name="millisecondsTimeout">The number of milliseconds to wait, or Timeout.Infinite (-1) to wait indefinitely.</param>
/// <param name="exitContext">
/// true to exit the synchronization domain for the context before the wait (if in a synchronized context), and reacquire it; otherwise, false.
/// </param>
/// <returns>
/// true when every work item in workItemResults has completed; otherwise false.
/// </returns>
public static bool WaitAll(
IWaitableResult [] waitableResults,
int millisecondsTimeout,
bool exitContext)
{
return WorkItem.WaitAll(waitableResults, millisecondsTimeout, exitContext, null);
}
/// <summary>
/// Wait for all work items to complete
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <param name="millisecondsTimeout">The number of milliseconds to wait, or Timeout.Infinite (-1) to wait indefinitely.</param>
/// <param name="exitContext">
/// true to exit the synchronization domain for the context before the wait (if in a synchronized context), and reacquire it; otherwise, false.
/// </param>
/// <param name="cancelWaitHandle">A cancel wait handle to interrupt the wait if needed</param>
/// <returns>
/// true when every work item in workItemResults has completed; otherwise false.
/// </returns>
public static bool WaitAll(
IWaitableResult[] waitableResults,
int millisecondsTimeout,
bool exitContext,
WaitHandle cancelWaitHandle)
{
return WorkItem.WaitAll(waitableResults, millisecondsTimeout, exitContext, cancelWaitHandle);
}
/// <summary>
/// Waits for any of the work items in the specified array to complete, cancel, or timeout
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <returns>
/// The array index of the work item result that satisfied the wait, or WaitTimeout if any of the work items has been canceled.
/// </returns>
public static int WaitAny(
IWaitableResult [] waitableResults)
{
return WaitAny(waitableResults, Timeout.Infinite, true);
}
/// <summary>
/// Waits for any of the work items in the specified array to complete, cancel, or timeout
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <param name="timeout">The number of milliseconds to wait, or a TimeSpan that represents -1 milliseconds to wait indefinitely. </param>
/// <param name="exitContext">
/// true to exit the synchronization domain for the context before the wait (if in a synchronized context), and reacquire it; otherwise, false.
/// </param>
/// <returns>
/// The array index of the work item result that satisfied the wait, or WaitTimeout if no work item result satisfied the wait and a time interval equivalent to millisecondsTimeout has passed or the work item has been canceled.
/// </returns>
public static int WaitAny(
IWaitableResult[] waitableResults,
TimeSpan timeout,
bool exitContext)
{
return WaitAny(waitableResults, (int)timeout.TotalMilliseconds, exitContext);
}
/// <summary>
/// Waits for any of the work items in the specified array to complete, cancel, or timeout
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <param name="timeout">The number of milliseconds to wait, or a TimeSpan that represents -1 milliseconds to wait indefinitely. </param>
/// <param name="exitContext">
/// true to exit the synchronization domain for the context before the wait (if in a synchronized context), and reacquire it; otherwise, false.
/// </param>
/// <param name="cancelWaitHandle">A cancel wait handle to interrupt the wait if needed</param>
/// <returns>
/// The array index of the work item result that satisfied the wait, or WaitTimeout if no work item result satisfied the wait and a time interval equivalent to millisecondsTimeout has passed or the work item has been canceled.
/// </returns>
public static int WaitAny(
IWaitableResult [] waitableResults,
TimeSpan timeout,
bool exitContext,
WaitHandle cancelWaitHandle)
{
return WaitAny(waitableResults, (int)timeout.TotalMilliseconds, exitContext, cancelWaitHandle);
}
/// <summary>
/// Waits for any of the work items in the specified array to complete, cancel, or timeout
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <param name="millisecondsTimeout">The number of milliseconds to wait, or Timeout.Infinite (-1) to wait indefinitely.</param>
/// <param name="exitContext">
/// true to exit the synchronization domain for the context before the wait (if in a synchronized context), and reacquire it; otherwise, false.
/// </param>
/// <returns>
/// The array index of the work item result that satisfied the wait, or WaitTimeout if no work item result satisfied the wait and a time interval equivalent to millisecondsTimeout has passed or the work item has been canceled.
/// </returns>
public static int WaitAny(
IWaitableResult [] waitableResults,
int millisecondsTimeout,
bool exitContext)
{
return WorkItem.WaitAny(waitableResults, millisecondsTimeout, exitContext, null);
}
/// <summary>
/// Waits for any of the work items in the specified array to complete, cancel, or timeout
/// </summary>
/// <param name="waitableResults">Array of work item result objects</param>
/// <param name="millisecondsTimeout">The number of milliseconds to wait, or Timeout.Infinite (-1) to wait indefinitely.</param>
/// <param name="exitContext">
/// true to exit the synchronization domain for the context before the wait (if in a synchronized context), and reacquire it; otherwise, false.
/// </param>
/// <param name="cancelWaitHandle">A cancel wait handle to interrupt the wait if needed</param>
/// <returns>
/// The array index of the work item result that satisfied the wait, or WaitTimeout if no work item result satisfied the wait and a time interval equivalent to millisecondsTimeout has passed or the work item has been canceled.
/// </returns>
public static int WaitAny(
IWaitableResult [] waitableResults,
int millisecondsTimeout,
bool exitContext,
WaitHandle cancelWaitHandle)
{
return WorkItem.WaitAny(waitableResults, millisecondsTimeout, exitContext, cancelWaitHandle);
}
/// <summary>
/// Creates a new WorkItemsGroup.
/// </summary>
/// <param name="concurrency">The number of work items that can be run concurrently</param>
/// <returns>A reference to the WorkItemsGroup</returns>
public IWorkItemsGroup CreateWorkItemsGroup(int concurrency)
{
IWorkItemsGroup workItemsGroup = new WorkItemsGroup(this, concurrency, _stpStartInfo);
return workItemsGroup;
}
/// <summary>
/// Creates a new WorkItemsGroup.
/// </summary>
/// <param name="concurrency">The number of work items that can be run concurrently</param>
/// <param name="wigStartInfo">A WorkItemsGroup configuration that overrides the default behavior</param>
/// <returns>A reference to the WorkItemsGroup</returns>
public IWorkItemsGroup CreateWorkItemsGroup(int concurrency, WIGStartInfo wigStartInfo)
{
IWorkItemsGroup workItemsGroup = new WorkItemsGroup(this, concurrency, wigStartInfo);
return workItemsGroup;
}
#region Fire Thread's Events
private void FireOnThreadInitialization()
{
if (null != _onThreadInitialization)
{
foreach (ThreadInitializationHandler tih in _onThreadInitialization.GetInvocationList())
{
try
{
tih();
}
catch (Exception e)
{
e.GetHashCode();
Debug.Assert(false);
throw;
}
}
}
}
private void FireOnThreadTermination()
{
if (null != _onThreadTermination)
{
foreach (ThreadTerminationHandler tth in _onThreadTermination.GetInvocationList())
{
try
{
tth();
}
catch (Exception e)
{
e.GetHashCode();
Debug.Assert(false);
throw;
}
}
}
}
#endregion
/// <summary>
/// This event is fired when a thread is created.
/// Use it to initialize a thread before the work items use it.
/// </summary>
public event ThreadInitializationHandler OnThreadInitialization
{
add { _onThreadInitialization += value; }
remove { _onThreadInitialization -= value; }
}
/// <summary>
/// This event is fired when a thread is terminating.
/// Use it for cleanup.
/// </summary>
public event ThreadTerminationHandler OnThreadTermination
{
add { _onThreadTermination += value; }
remove { _onThreadTermination -= value; }
}
internal void CancelAbortWorkItemsGroup(WorkItemsGroup wig)
{
foreach (ThreadEntry threadEntry in _workerThreads.Values)
{
WorkItem workItem = threadEntry.CurrentWorkItem;
if (null != workItem &&
workItem.WasQueuedBy(wig) &&
!workItem.IsCanceled)
{
threadEntry.CurrentWorkItem.GetWorkItemResult().Cancel(true);
}
}
}
#endregion
#region Properties
/// <summary>
/// Get/Set the lower limit of threads in the pool.
/// </summary>
public int MinThreads
{
get
{
ValidateNotDisposed();
return _stpStartInfo.MinWorkerThreads;
}
set
{
Debug.Assert(value >= 0);
Debug.Assert(value <= _stpStartInfo.MaxWorkerThreads);
if (_stpStartInfo.MaxWorkerThreads < value)
{
_stpStartInfo.MaxWorkerThreads = value;
}
_stpStartInfo.MinWorkerThreads = value;
StartOptimalNumberOfThreads();
}
}
/// <summary>
/// Get/Set the upper limit of threads in the pool.
/// </summary>
public int MaxThreads
{
get
{
ValidateNotDisposed();
return _stpStartInfo.MaxWorkerThreads;
}
set
{
Debug.Assert(value > 0);
Debug.Assert(value >= _stpStartInfo.MinWorkerThreads);
if (_stpStartInfo.MinWorkerThreads > value)
{
_stpStartInfo.MinWorkerThreads = value;
}
_stpStartInfo.MaxWorkerThreads = value;
StartOptimalNumberOfThreads();
}
}
/// <summary>
/// Get the number of threads in the thread pool.
/// Should be between the lower and the upper limits.
/// </summary>
public int ActiveThreads
{
get
{
ValidateNotDisposed();
return _workerThreads.Count;
}
}
/// <summary>
/// Get the number of busy (not idle) threads in the thread pool.
/// </summary>
public int InUseThreads
{
get
{
ValidateNotDisposed();
return _inUseWorkerThreads;
}
}
/// <summary>
/// Returns true if the current running work item has been cancelled.
/// Must be used within the work item's callback method.
/// The work item should sample this value in order to know if it
/// needs to quit before its completion.
/// </summary>
public static bool IsWorkItemCanceled
{
get
{
return CurrentThreadEntry.CurrentWorkItem.IsCanceled;
}
}
/// <summary>
/// Checks if the work item has been cancelled, and if yes then abort the thread.
/// Can be used with Cancel and timeout
/// </summary>
public static void AbortOnWorkItemCancel()
{
if (IsWorkItemCanceled)
{
Thread.CurrentThread.Abort();
}
}
/// <summary>
/// Thread Pool start information (readonly)
/// </summary>
public STPStartInfo STPStartInfo
{
get
{
return _stpStartInfo.AsReadOnly();
}
}
public bool IsShuttingdown
{
get { return _shutdown; }
}
/// <summary>
/// Return the local calculated performance counters
/// Available only if STPStartInfo.EnableLocalPerformanceCounters is true.
/// </summary>
public ISTPPerformanceCountersReader PerformanceCountersReader
{
get { return (ISTPPerformanceCountersReader)_localPCs; }
}
#endregion
#region IDisposable Members
public void Dispose()
{
if (!_isDisposed)
{
if (!_shutdown)
{
Shutdown();
}
if (null != _shuttingDownEvent)
{
_shuttingDownEvent.Close();
_shuttingDownEvent = null;
}
_workerThreads.Clear();
if (null != _isIdleWaitHandle)
{
_isIdleWaitHandle.Close();
_isIdleWaitHandle = null;
}
if (_stpStartInfo.EnableLocalPerformanceCounters)
_localPCs.Dispose();
_isDisposed = true;
}
}
private void ValidateNotDisposed()
{
if(_isDisposed)
{
throw new ObjectDisposedException(GetType().ToString(), "The SmartThreadPool has been shutdown");
}
}
#endregion
#region WorkItemsGroupBase Overrides
/// <summary>
/// Get/Set the maximum number of work items that execute cocurrency on the thread pool
/// </summary>
public override int Concurrency
{
get { return MaxThreads; }
set { MaxThreads = value; }
}
/// <summary>
/// Get the number of work items in the queue.
/// </summary>
public override int WaitingCallbacks
{
get
{
ValidateNotDisposed();
return _workItemsQueue.Count;
}
}
/// <summary>
/// Get an array with all the state objects of the currently running items.
/// The array represents a snap shot and impact performance.
/// </summary>
public override object[] GetStates()
{
object[] states = _workItemsQueue.GetStates();
return states;
}
/// <summary>
/// WorkItemsGroup start information (readonly)
/// </summary>
public override WIGStartInfo WIGStartInfo
{
get { return _stpStartInfo.AsReadOnly(); }
}
/// <summary>
/// Start the thread pool if it was started suspended.
/// If it is already running, this method is ignored.
/// </summary>
public override void Start()
{
if (!_isSuspended)
{
return;
}
_isSuspended = false;
ICollection workItemsGroups = _workItemsGroups.Values;
foreach (WorkItemsGroup workItemsGroup in workItemsGroups)
{
workItemsGroup.OnSTPIsStarting();
}
StartOptimalNumberOfThreads();
}
/// <summary>
/// Cancel all work items using thread abortion
/// </summary>
/// <param name="abortExecution">True to stop work items by raising ThreadAbortException</param>
public override void Cancel(bool abortExecution)
{
_canceledSmartThreadPool.IsCanceled = true;
_canceledSmartThreadPool = new CanceledWorkItemsGroup();
ICollection workItemsGroups = _workItemsGroups.Values;
foreach (WorkItemsGroup workItemsGroup in workItemsGroups)
{
workItemsGroup.Cancel(abortExecution);
}
if (abortExecution)
{
foreach (ThreadEntry threadEntry in _workerThreads.Values)
{
WorkItem workItem = threadEntry.CurrentWorkItem;
if (null != workItem &&
threadEntry.AssociatedSmartThreadPool == this &&
!workItem.IsCanceled)
{
threadEntry.CurrentWorkItem.GetWorkItemResult().Cancel(true);
}
}
}
}
/// <summary>
/// Wait for the thread pool to be idle
/// </summary>
public override bool WaitForIdle(int millisecondsTimeout)
{
ValidateWaitForIdle();
return STPEventWaitHandle.WaitOne(_isIdleWaitHandle, millisecondsTimeout, false);
}
/// <summary>
/// This event is fired when all work items are completed.
/// (When IsIdle changes to true)
/// This event only work on WorkItemsGroup. On SmartThreadPool
/// it throws the NotImplementedException.
/// </summary>
public override event WorkItemsGroupIdleHandler OnIdle
{
add
{
throw new NotImplementedException("This event is not implemented in the SmartThreadPool class. Please create a WorkItemsGroup in order to use this feature.");
//_onIdle += value;
}
remove
{
throw new NotImplementedException("This event is not implemented in the SmartThreadPool class. Please create a WorkItemsGroup in order to use this feature.");
//_onIdle -= value;
}
}
internal override void PreQueueWorkItem()
{
ValidateNotDisposed();
}
#endregion
#region Join, Choice, Pipe, etc.
/// <summary>
/// Executes all actions in parallel.
/// Returns when they all finish.
/// </summary>
/// <param name="actions">Actions to execute</param>
public void Join(IEnumerable<Action> actions)
{
WIGStartInfo wigStartInfo = new WIGStartInfo { StartSuspended = true };
IWorkItemsGroup workItemsGroup = CreateWorkItemsGroup(int.MaxValue, wigStartInfo);
foreach (Action action in actions)
{
workItemsGroup.QueueWorkItem(action);
}
workItemsGroup.Start();
workItemsGroup.WaitForIdle();
}
/// <summary>
/// Executes all actions in parallel.
/// Returns when they all finish.
/// </summary>
/// <param name="actions">Actions to execute</param>
public void Join(params Action[] actions)
{
Join((IEnumerable<Action>)actions);
}
private class ChoiceIndex
{
public int _index = -1;
}
/// <summary>
/// Executes all actions in parallel
/// Returns when the first one completes
/// </summary>
/// <param name="actions">Actions to execute</param>
public int Choice(IEnumerable<Action> actions)
{
WIGStartInfo wigStartInfo = new WIGStartInfo { StartSuspended = true };
IWorkItemsGroup workItemsGroup = CreateWorkItemsGroup(int.MaxValue, wigStartInfo);
ManualResetEvent anActionCompleted = new ManualResetEvent(false);
ChoiceIndex choiceIndex = new ChoiceIndex();
int i = 0;
foreach (Action action in actions)
{
Action act = action;
int value = i;
workItemsGroup.QueueWorkItem(() => { act(); Interlocked.CompareExchange(ref choiceIndex._index, value, -1); anActionCompleted.Set(); });
++i;
}
workItemsGroup.Start();
anActionCompleted.WaitOne();
anActionCompleted.Dispose();
return choiceIndex._index;
}
/// <summary>
/// Executes all actions in parallel
/// Returns when the first one completes
/// </summary>
/// <param name="actions">Actions to execute</param>
public int Choice(params Action[] actions)
{
return Choice((IEnumerable<Action>)actions);
}
/// <summary>
/// Executes actions in sequence asynchronously.
/// Returns immediately.
/// </summary>
/// <param name="pipeState">A state context that passes </param>
/// <param name="actions">Actions to execute in the order they should run</param>
public void Pipe<T>(T pipeState, IEnumerable<Action<T>> actions)
{
WIGStartInfo wigStartInfo = new WIGStartInfo { StartSuspended = true };
IWorkItemsGroup workItemsGroup = CreateWorkItemsGroup(1, wigStartInfo);
foreach (Action<T> action in actions)
{
Action<T> act = action;
workItemsGroup.QueueWorkItem(() => act(pipeState));
}
workItemsGroup.Start();
workItemsGroup.WaitForIdle();
}
/// <summary>
/// Executes actions in sequence asynchronously.
/// Returns immediately.
/// </summary>
/// <param name="pipeState"></param>
/// <param name="actions">Actions to execute in the order they should run</param>
public void Pipe<T>(T pipeState, params Action<T>[] actions)
{
Pipe(pipeState, (IEnumerable<Action<T>>)actions);
}
#endregion
}
#endregion
}