public void TestThreeTasksOnTwoThreadsPreemptingEachOther()
{
int numOfThreads = 2;
SimpleTaskScheduler taskScheduler = SimpleTaskScheduler.CreatePreemptive(numOfThreads);
SimpleTaskScheduler.ExecutionToken token1 = taskScheduler.GetExecutionToken();
SimpleTaskScheduler.ExecutionToken token2 = taskScheduler.GetExecutionToken();
SimpleTaskScheduler.ExecutionToken token3 = taskScheduler.GetExecutionToken();
Object resource = new object();
Task t1 = CreateTaskWithResourceLock(id: 1, token: token1, resource: resource);
Task t2 = CreateTaskWithResourceLock(id: 2, token: token2, resource: resource);
Task t3 = CreateTask(id: 3, token: token3);
taskScheduler.Register(t1, 5, 2500, token1);
taskScheduler.Register(t2, 4, 2500, token2);
taskScheduler.Register(t3, 3, 2500, token3);
t1.Start(taskScheduler);
Task.Delay(500).Wait();
t2.Start(taskScheduler);
t3.Start(taskScheduler);
Task.Delay(5000).Wait();
Assert.AreEqual(taskScheduler.CurrentlyExecutingTasksCount(), 0);
}
internal override void Execute()
{
int currentlyExecutingTasksCount = scheduler.CurrentlyExecutingTasksCount();
Task minPriorityNonExecutingTask = scheduler.FindMinimumPriorityNonExecutingTask();
if (minPriorityNonExecutingTask == null)
{
return;
}
if (currentlyExecutingTasksCount < scheduler.MaxParallelTasks)
{
//start min priority non executing task, we have a free thread
scheduler.ContinueStartTask(task: minPriorityNonExecutingTask, threadId: scheduler.FindFirstFreeThread());
}
else if (scheduler.IsPreemptive)
{
//search for task which could be stopped
Task maxPriorityExecutingTask = scheduler.FindMaximumPriorityExecutingTask();
if (scheduler.ComparePriorities(minPriorityNonExecutingTask, maxPriorityExecutingTask) < 0)
{
int threadId = scheduler.GetThreadOfTask(maxPriorityExecutingTask);
scheduler.PauseTask(maxPriorityExecutingTask);
scheduler.ContinueStartTask(minPriorityNonExecutingTask, threadId);
}
}
}
public void TestTwoTasksWithNoResourceLocking()
{
int numOfThreads = 1;
SimpleTaskScheduler taskScheduler = SimpleTaskScheduler.CreatePreemptive(numOfThreads);
SimpleTaskScheduler.ExecutionToken token1 = taskScheduler.GetExecutionToken();
SimpleTaskScheduler.ExecutionToken token2 = taskScheduler.GetExecutionToken();
Task t1 = CreateTask(id: 1, token: token1);
Task t2 = CreateTask(id: 2, token: token2);
taskScheduler.Register(t1, 5, 2500, token1);
taskScheduler.Register(t2, 4, 2500, token2);
t1.Start(taskScheduler);
Task.Delay(500).Wait();
t2.Start(taskScheduler);
Assert.AreEqual(taskScheduler.CurrentlyExecutingTasksCount(), 1);
}