public async Task ExecutesOneItemFromBucketAtATime()
{
long sum = 0;
ManualResetEvent mre = new ManualResetEvent(false);
WorkScheduler <int> scheduler = new WorkScheduler <int>(work => {
Interlocked.Add(ref sum, work);
mre.WaitOne();
return(Task.CompletedTask);
});
scheduler.Enqueue(1, 0);
scheduler.Enqueue(2, 1);
scheduler.Enqueue(3, 1);
Assert.Equal(1, scheduler.PendingWorkItems);
SpinWait.SpinUntil(() => Interlocked.Read(ref sum) == 3);
Assert.Equal(3, sum);
mre.Set();
SpinWait.SpinUntil(() => Interlocked.Read(ref sum) == 6);
Assert.Equal(6, sum);
Assert.Equal(0, scheduler.PendingWorkItems);
var workItems = await scheduler.StopAndWaitForCompletionAsync();
Assert.Empty(workItems);
Assert.Equal(6, sum);
}
public async Task RetrievesNonScheduledWorkInSortedOrder()
{
long sum = 0;
ManualResetEvent mre = new ManualResetEvent(false);
WorkScheduler <int> scheduler = new WorkScheduler <int>(work => {
Interlocked.Add(ref sum, work);
mre.WaitOne();
return(Task.CompletedTask);
}, maxDegreeOfParallelism: 1);
scheduler.Enqueue(1, 0, bucketPriority: 1);
scheduler.Enqueue(2, 0);
scheduler.Enqueue(3, 1, bucketPriority: 2);
scheduler.Enqueue(4, 2);
scheduler.Enqueue(5, 1, bucketPriority: 3);
scheduler.Enqueue(6, 2);
Assert.Equal(5, scheduler.PendingWorkItems);
SpinWait.SpinUntil(() => Interlocked.Read(ref sum) == 1);
Assert.Equal(1, sum);
Assert.Equal(5, scheduler.PendingWorkItems);
_ = Task.Run(async() => { await Task.Delay(100); mre.Set(); });
var workItems = await scheduler.StopAndWaitForCompletionAsync();
Assert.Equal(0, scheduler.PendingWorkItems);
Assert.Equal(1, sum);
Assert.Equal(new[] { 5, 3, 2, 4, 6 }, workItems);
}
public async Task RetrievesNonScheduledWork()
{
long sum = 0;
ManualResetEvent mre = new ManualResetEvent(false);
WorkScheduler <int> scheduler = new WorkScheduler <int>(work => {
Interlocked.Add(ref sum, work);
mre.WaitOne();
return(Task.CompletedTask);
});
scheduler.Enqueue(1, 0);
scheduler.Enqueue(2, 0);
scheduler.Enqueue(3, 1);
scheduler.Enqueue(4, 1);
Assert.Equal(2, scheduler.PendingWorkItems);
SpinWait.SpinUntil(() => Interlocked.Read(ref sum) == 4);
Assert.Equal(4, sum);
_ = Task.Run(async() => { await Task.Delay(100); mre.Set(); });
var workItems = await scheduler.StopAndWaitForCompletionAsync();
Assert.Equal(0, scheduler.PendingWorkItems);
Assert.Equal(4, sum);
Assert.Equal(new[] { 2, 4 }, workItems);
}
public async Task StopsIfNoWorkIsPending()
{
long sum = 0;
WorkScheduler <int> scheduler = new WorkScheduler <int>(work => {
Interlocked.Add(ref sum, work);
return(Task.CompletedTask);
});
var workItems = await scheduler.StopAndWaitForCompletionAsync();
Assert.Empty(workItems);
Assert.Equal(0, scheduler.PendingWorkItems);
}
public async Task ExecutesWork()
{
int sum = 0;
WorkScheduler <int> scheduler = new WorkScheduler <int>(work => {
Interlocked.Add(ref sum, work);
return(Task.CompletedTask);
});
scheduler.Enqueue(1, 0);
scheduler.Enqueue(2, 1);
scheduler.Enqueue(3, 2);
scheduler.Enqueue(4, 3);
Assert.Equal(0, scheduler.PendingWorkItems);
var workItems = await scheduler.StopAndWaitForCompletionAsync();
Assert.Empty(workItems);
Assert.Equal(10, sum);
}
public async Task HonorsUserSpecifiedPriority()
{
long value = 0;
ManualResetEvent mre = new ManualResetEvent(false);
WorkScheduler <int> scheduler = new WorkScheduler <int>(work => {
Interlocked.Add(ref value, work);
mre.WaitOne();
mre.Reset();
return(Task.CompletedTask);
}, maxDegreeOfParallelism: 1);
scheduler.Enqueue(1, 0, bucketPriority: 1);
scheduler.Enqueue(2, 0, bucketPriority: 1);
scheduler.Enqueue(3, 1, bucketPriority: 3);
scheduler.Enqueue(4, 2, bucketPriority: 2);
scheduler.Enqueue(5, 1, bucketPriority: 3);
scheduler.Enqueue(6, 2, bucketPriority: 2);
// 1 goes first as it is the first one enqueued
// then follow 3, 5, 4, 6, 2
Assert.Equal(5, scheduler.PendingWorkItems);
SpinWait.SpinUntil(() => Interlocked.Read(ref value) == 1);
Assert.Equal(1, value);
value = 0;
Assert.Equal(5, scheduler.PendingWorkItems);
mre.Set();
SpinWait.SpinUntil(() => Interlocked.Read(ref value) == 3);
Assert.Equal(3, value);
value = 0;
Assert.Equal(4, scheduler.PendingWorkItems);
mre.Set();
SpinWait.SpinUntil(() => Interlocked.Read(ref value) == 5);
Assert.Equal(5, value);
value = 0;
Assert.Equal(3, scheduler.PendingWorkItems);
mre.Set();
SpinWait.SpinUntil(() => Interlocked.Read(ref value) == 4);
Assert.Equal(4, value);
value = 0;
Assert.Equal(2, scheduler.PendingWorkItems);
mre.Set();
SpinWait.SpinUntil(() => Interlocked.Read(ref value) == 6);
Assert.Equal(6, value);
value = 0;
Assert.Equal(1, scheduler.PendingWorkItems);
mre.Set();
SpinWait.SpinUntil(() => Interlocked.Read(ref value) == 2);
Assert.Equal(2, value);
value = 0;
Assert.Equal(0, scheduler.PendingWorkItems);
mre.Set();
var workItems = await scheduler.StopAndWaitForCompletionAsync();
Assert.Empty(workItems);
Assert.Equal(0, scheduler.PendingWorkItems);
}