Bar Arnon i3arnon

Efficiency driven developer. Ex-Microsoft (ADX, AATP, ATA). Ex-Aorato (Acquired by Microsoft).

i3arnon / 03-TimerContention-02.cs

Created October 6, 2015 20:53

Timer.Change takes a lock on a singleton instance.

	internal bool Change(uint dueTime, uint period)
	{
	bool success;

	lock (TimerQueue.Instance)
	{
	if (m_canceled)
	throw new ObjectDisposedException(null, Environment.GetResourceString("ObjectDisposed_Generic"));

	// prevent ThreadAbort while updating state

i3arnon / 03-TimerContention-02.cs

Last active October 6, 2015 21:06

Timer.Change takes a lock on a singleton instance (http://referencesource.microsoft.com/#mscorlib/system/threading/timer.cs)

	internal bool Change(uint dueTime, uint period)
	{
	bool success;

	lock (TimerQueue.Instance) // Global lock.
	{
	if (m_canceled)
	throw new ObjectDisposedException(null, Environment.GetResourceString("ObjectDisposed_Generic"));

	// prevent ThreadAbort while updating state

i3arnon / 03-TimerContention-03.cs

Created October 6, 2015 20:59

CollectiveTimer reduces timer allocations.

	public class CollectiveTimer<T>
	{
	private readonly ConcurrentQueue<QueueItem> _queue;
	public CollectiveTimer(Action<T> action, TimeSpan timeout, CancellationToken cancellationToken)
	{
	_queue = new ConcurrentQueue<QueueItem>();
	Task.Run(async () =>
	{
	while (!cancellationToken.IsCancellationRequested)
	{

i3arnon / 03-TimerContention-04.cs

Created October 6, 2015 21:01

CollectiveTimer usage

	var collectiveTimer = new CollectiveTimer<CancellationTokenSource>(
	cts => cts.Cancel(),
	TimeSpan.FromMilliseconds(200),
	cancellationToken);

i3arnon / 02-LongRunning-01.cs

Created October 6, 2015 21:12

	Task<Task> task = Task.Factory.StartNew(async () =>
	{
	while (IsEnabled)
	{
	await FooAsync();
	await Task.Delay(TimeSpan.FromSeconds(10));
	}
	}, TaskCreationOptions.LongRunning);

	Task actualTask = task.Unwrap();

i3arnon / 02-LongRunning-02.cs

Created October 6, 2015 21:14

ThreadPoolTaskScheduler.QueueTask creates a new thread for TaskCreationOptions.LongRunning

	protected internal override void QueueTask(Task task)
	{
	if ((task.Options & TaskCreationOptions.LongRunning) != 0)
	{
	// Run LongRunning tasks on their own dedicated thread.
	Thread thread = new Thread(s_longRunningThreadWork);
	thread.IsBackground = true; // Keep this thread from blocking process shutdown
	thread.Start(task);
	}
	else

i3arnon / 02-LongRunning-03.cs

Created October 6, 2015 21:16

Task.Run over Task.Factory.StartNew

	Task task = Task.Run(async () =>
	{
	while (IsEnabled)
	{
	await FooAsync();
	await Task.Delay(TimeSpan.FromSeconds(10));
	}
	});

i3arnon / 01-LogicalOperationStack-01.cs

Created October 6, 2015 21:20

	static void Main()
	{
	OuterOperationAsync().Wait();
	}

	static async Task OuterOperationAsync()
	{
	Console.WriteLine(LogicalFlow.CurrentOperationId);
	using (LogicalFlow.StartScope())
	{

i3arnon / 01-LogicalOperationStack-02.cs

Created October 6, 2015 21:21

LogicalFlow - A wrapper over LogicalOperationStack

	public static class LogicalFlow
	{
	public static Guid CurrentOperationId
	{
	get
	{
	return Trace.CorrelationManager.LogicalOperationStack.Count > 0
	? (Guid) Trace.CorrelationManager.LogicalOperationStack.Peek()
	: Guid.Empty;
	}

i3arnon / 01-LogicalOperationStack-03.txt

Created October 6, 2015 21:22

Output using LogicalOperationStack