public async Task Test_FdbCounter_Can_Increment_And_SetTotal()
{
using (var db = await OpenTestPartitionAsync())
{
var location = db.Root["counters"]["simple"];
await CleanLocation(db, location);
var counter = new FdbHighContentionCounter(location);
await db.WriteAsync(async tr => await counter.Add(tr, 100), this.Cancellation);
var res = await db.ReadAsync(tr => counter.GetSnapshot(tr), this.Cancellation);
Assert.That(res, Is.EqualTo(100));
await db.WriteAsync(async tr => await counter.Add(tr, -10), this.Cancellation);
res = await db.ReadAsync(tr => counter.GetSnapshot(tr), this.Cancellation);
Assert.That(res, Is.EqualTo(90));
await db.WriteAsync(async tr => await counter.SetTotal(tr, 500), this.Cancellation);
res = await db.ReadAsync(tr => counter.GetSnapshot(tr), this.Cancellation);
Assert.That(res, Is.EqualTo(500));
}
}
public async Task Bench_FdbCounter_Increment_Sequentially()
{
const int N = 100;
using (var db = await OpenTestPartitionAsync())
{
var location = db.Root["counters"]["big"];
await CleanLocation(db, location);
var c = new FdbHighContentionCounter(location);
Log("Doing " + N + " inserts in one thread...");
var sw = Stopwatch.StartNew();
for (int i = 0; i < N; i++)
{
await db.WriteAsync(async tr => await c.Add(tr, 1), this.Cancellation);
}
sw.Stop();
Log("> " + N + " completed in " + sw.Elapsed.TotalMilliseconds.ToString("N1") + " ms (" + (sw.Elapsed.TotalMilliseconds * 1000 / N).ToString("N0") + " µs/add)");
#if DEBUG
await DumpSubspace(db, location);
#endif
var res = await db.ReadAsync(async tr => await c.GetSnapshot(tr), this.Cancellation);
Assert.That(res, Is.EqualTo(N));
}
}
public async Task Bench_FdbCounter_Increment_Concurrently()
{
const int B = 100;
// repeat the process 10 times...
foreach (int W in new [] { 1, 2, 5, 10, 20, 50, 100 })
{
int N = B * W;
using (var db = await OpenTestPartitionAsync())
{
var location = db.Root["counters"]["big"][W.ToString()];
await CleanLocation(db, location);
var c = new FdbHighContentionCounter(location);
Log("Doing " + W + " x " + B + " inserts in " + W + " threads...");
var signal = new TaskCompletionSource <object>();
var workers = Enumerable.Range(0, W)
.Select(async(id) =>
{
await signal.Task.ConfigureAwait(false);
for (int i = 0; i < B; i++)
{
await db.WriteAsync(async tr => await c.Add(tr, 1), this.Cancellation);
}
}).ToArray();
var sw = Stopwatch.StartNew();
// start
ThreadPool.UnsafeQueueUserWorkItem((_) => signal.TrySetResult(null), null);
// wait
await Task.WhenAll(workers);
sw.Stop();
Log("> " + N + " completed in " + sw.Elapsed.TotalMilliseconds.ToString("N1") + " ms (" + (sw.Elapsed.TotalMilliseconds * 1000 / B).ToString("N0") + " µs/add)");
long n = await db.ReadAsync(tr => c.GetSnapshot(tr), this.Cancellation);
if (n != N)
{ // fail
await DumpSubspace(db, location);
Assert.That(n, Is.EqualTo(N), "Counter value does not match (first call)");
}
// wait a bit, in case there was some coalesce still running...
await Task.Delay(200);
n = await db.ReadAsync(tr => c.GetSnapshot(tr), this.Cancellation);
if (n != N)
{ // fail
await DumpSubspace(db, location);
Assert.That(n, Is.EqualTo(N), "Counter value does not match (second call)");
}
}
}
}
