Memory leak in EndPoint channels bugfix

src/Proto.Remote/Endpoints/Endpoint.cs

@@ -375,17 +375,19 @@ private void RejectRemoteDeliver(RemoteDeliver env)
 
  private async Task RunAsync()
  {
+ var waiter = new MultiTaskReuseWaiter<bool>(
+ () => _remoteDelivers.Reader.WaitToReadAsync(CancellationToken),
+ () => _remotePriorityDelivers.Reader.WaitToReadAsync(CancellationToken));
+
  while (!CancellationToken.IsCancellationRequested)
  {
  try
  {
  var messages = new List<RemoteDeliver>(RemoteConfig.EndpointWriterOptions.EndpointWriterBatchSize);
-
  while (true)
  {
- var t1 = _remoteDelivers.Reader.WaitToReadAsync(CancellationToken).AsTask();
- var t2 = _remotePriorityDelivers.Reader.WaitToReadAsync(CancellationToken).AsTask();
- await Task.WhenAny(t1, t2);
+ await waiter.WaitAnyAsync();
+
  var i = 0;
  while (true)
  {
@@ -571,4 +573,38 @@ private MessageBatch CreateBatch(IReadOnlyCollection<RemoteDeliver> m)
  // Logger.LogTrace("[{SystemAddress}] Sending {Count} envelopes for {Address}", System.Address, envelopes.Count, Address);
  return batch;
  }
+
+ /// <summary>
+ /// Preserves non completed Tasks between <see cref="WaitAnyAsync"/> calls.
+ /// This is necessary to prevent memory leak https://github.com/asynkron/protoactor-dotnet/issues/2110 
+ /// </summary>
+ class MultiTaskReuseWaiter<T>
+ {
+ private readonly Func<ValueTask<T>>[] _taskFactories;
+ private readonly Task<T>?[] _tasks;
+
+ public MultiTaskReuseWaiter(params Func<ValueTask<T>>[] taskFactories)
+ {
+ _taskFactories = taskFactories;
+ _tasks = new Task<T>?[taskFactories.Length];
+ }
+
+ public async ValueTask<T> WaitAnyAsync()
+ {
+ for (var i = 0; i < _taskFactories.Length; i++)
+ {
+ if (_tasks[i]?.IsCompleted == false)
+ continue;
+
+ var vt = _taskFactories[i].Invoke();
+ if (vt.IsCompleted)
+ return await vt;
+
+ _tasks[i] = vt.AsTask();
+ }
+
+ return await await Task.WhenAny(_tasks!);
+ }
+
+ }
 }