Azure WebJob Scale Out only 2 Jobs working - azure

Question

I got a small WebJob running in 3 instances, the WebJob is triggered by ServiceBusTrigger, each job takes about 20 seconds (I added a sleep for testing).
Now i add 3 items to the ServiceBus Queue but only 2 WebJob Instances are working.
What is the third instance doing and how can i get the instance to also work on the queue?
My code is very basic:
public class Functions
{
// This function will get triggered/executed when a new message is written
// on an Azure Queue called queue.
public static void ProcessQueueMessage([ServiceBusTrigger("jobs2")] string message, TextWriter log)
{
string url = "https://requestb.in/xxxxx";
log.WriteLine(message);
log.WriteLine("gotmsg");
Thread.Sleep(20000);
log.WriteLine("sending");
string postData = "test=" + message;
Console.WriteLine(postData);
System.Net.WebRequest req = System.Net.WebRequest.Create(url);
//Add these, as we're doing a POST
req.ContentType = "application/x-www-form-urlencoded";
req.Method = "POST";
//We need to count how many bytes we're sending. Post'ed Faked Forms should be name=value&
byte[] bytes = System.Text.Encoding.ASCII.GetBytes(postData);
req.ContentLength = bytes.Length;
System.IO.Stream os = req.GetRequestStream();
os.Write(bytes, 0, bytes.Length); //Push it out there
os.Close();
System.Net.WebResponse resp = req.GetResponse();
if (resp == null) return;
System.IO.StreamReader sr = new System.IO.StreamReader(resp.GetResponseStream());
log.WriteLine(sr.ReadToEnd().Trim());
}
}

Answer 1

What is the third instance doing and how can i get the instance to also work on the queue?
The third instance shoud work as default. I assume Azure WebApp uses the specified LoadBalance strategy for multiple instances. And it seems that we have no way to config the LoadBalance strategy. In you case it seems that 3 message is not enough for test that. Please have a try to test it with more message. And I test it on my side, it works correctly. The following is the test code for sending message I used.
QueueClient.CreateFromConnectionString("connection string", QueueName);
for (int i = 0; i < 20; i++)
{
var sendMessage = new BrokeredMessage("test message"+i);
client.Send(sendMessage);
}