bool _run; //member of service class

//in OnStart
_run = true;

//in a method on some other thread
while ((yourLoopCondition) & _run)
{
  //do stuff
  foreach (thing in things)
  {
    //do more stuff
    if (!_run) break;
  }
}
if (!_run) CleanUp();

//in OnStop
_run = false;

// signal all threads to stop
this.AllThreadsStopSignal.Set();

if (logThreads.IsDebugEnabled)
	logThreads.Debug ("Stop workers");

// remember the time of the signal
DateTime signalTime = DateTime.Now;

// create an array of workers to be stopped
List<IServiceWorker> workersToBeStopped = new List<IServiceWorker> (workers);

while (true)
{
	// wait for some time
	Thread.Sleep (1000);

	// go through the list and see if any workers have stopped
	int i = 0;
	while (i < workersToBeStopped.Count)
	{
		IServiceWorker workerToBeStopped = workersToBeStopped [i];

		if (log.IsDebugEnabled)
			log.Debug (String.Format (System.Globalization.CultureInfo.InvariantCulture,
				"Stopping worker '{0}'. Worker state={1}",
				workerToBeStopped.WorkerDescription,
				workerToBeStopped.WorkerState));

		bool stopped = workerToBeStopped.JoinThread (TimeSpan.Zero);

		// if stopped, remove it from the list
		if (stopped)
		{
			workersToBeStopped.RemoveAt (i);
			if (log.IsDebugEnabled)
				log.Debug (String.Format (System.Globalization.CultureInfo.InvariantCulture,
					"Worker '{0}' was stopped.", workerToBeStopped.WorkerDescription));
		}
		else
		{
			i++;
			if (log.IsDebugEnabled)
				log.Debug (String.Format (System.Globalization.CultureInfo.InvariantCulture,
					"Worker '{0}' could not be stopped, will try again later. Worker state={1}",
					workerToBeStopped.WorkerDescription,
					workerToBeStopped.WorkerState));
		}
	}

	// if all workers were stopped, exit from the loop
	if (workersToBeStopped.Count == 0)
		break;

	// check if the duration of stopping has exceeded maximum time
	DateTime nowTime = DateTime.Now;
	TimeSpan duration = nowTime - signalTime;

	if (duration > serviceCustomization.ThreadTerminationMaxDuration)
	{
		// execute forced abortion of all workers which have not stopped
		foreach (IServiceWorker worker in workersToBeStopped)
		{
			try
			{
				log.Warn (String.Format (System.Globalization.CultureInfo.InvariantCulture,
					"Aborting worker '{0}.", worker.WorkerDescription));
				worker.Abort ();
				log.Warn (String.Format (System.Globalization.CultureInfo.InvariantCulture,
					"Worker '{0}' aborted.", worker.WorkerDescription));
			}
			catch (ThreadStateException ex)
			{
				log.Warn (String.Format (System.Globalization.CultureInfo.InvariantCulture,
					"Worker '{0}' could not be aborted.", worker.WorkerDescription), ex);
			}
		}
		break;
	}
}