Receiving events from event hub was blocked.

In our Cloud Service project, we have 2 instances for work role (deploy to Azure), the work role is consume events from the EventHub using EventProcessorHost(host name is RoleInstance name).

For sending events:

    var client = EventHubClient.CreateFromConnectionString(serviceBusConnectionString, hubName);

           while (true)

            {

               var eventData =newEventData(Encoding.UTF8.GetBytes("test")) {PartitionKey = "key"};

                    eventData.Properties.Add("time",DateTime.UtcNow);

                client.SendAsync(eventData).Wait();

                Thread.Sleep(50);

            }

Each 50ms, we send one event (event1, 2,3 …….);

For receiving data:    

 publicasyncTask ProcessEventsAsync(PartitionContext context, IEnumerable<EventData> events)

        {

            //when we get the event, so we can view the log

           Trace.WriteLine(“got events”);

           foreach (var eventData in events)

            {

                // handle the event

               Task.Delay(12000).Wait();

            }

           await ContextCheckpointAsync(context);

        }

We add thedelay for event operation.

It seems that we cannot receive data in time from the log, seems event6 was blocked for the Event5 delay, after the 12ms, we can receive event6 from the EventHub, and the Event6 delay is 40s(from the log, we send event6 to Hub at 35:10, but we get from Hub at 35:50),

So I wonder to know the maximum number of threads are working on processing fot the EventProcessorHost? Depends on the Partitions?

And is there any way to receiving events in time?