SendLocal clarification

1

I have a scenario where I can send 1000’s of commands in a loop
At the moment I am using SendLocal as they are processed on the same endpoint
On reading about concurrency and batching of sending messages, do I need to consider concurrencey with SendLocal? Does SendLocal send immediately or batch the sending?
Or am I better batching commands and Sending them immediately?

2

By default, all send operations (including SendLocal) are batched by the sending pipeline. That means if you have code like the following in your handler:

async Task Handle( MyMessage m, IMessageHandlerContext c )
{
   var outgoing = new List<Task>();
   for(i = 0; i < 1000; i++ )
   {
      c.SendLocal(new LocalMessage());
   }
   await Task.WhenAll(outgoing)
}

All 1000 messages will be delivered when completing the incoming message processing in a batch if the transport supports batching; otherwise, in a best-effort kind of approach, but always at the end.

You can use immediate dispatch to influence that behavior.

3

Thanks, I just hit the batching limits on Azure as your reply came
I see there is no way to sendlocal immediately so would need to use send
Is there any advantage of using SendLocal over Send?

4

Send requires routing information to be provided.
SendLocal does not.
Aside from that, both operation are identical.

5

thanks for the clarification. From what I can tell, there is no option to use sendlocal immediately though, correct?

6

You can provide SendOptions. See example.

7

Not that I can see with SendLocal

8

SendLocal is a shortcut for:

var options = new SendOptions();
options.RouteToThisEndpoint();

context.Send( myMessage, options);

With that in mind, you can do:

var options = new SendOptions();
options.RouteToThisEndpoint();
options.RequireImmediateDispatch();

context.Send( myMessage, options);

To have an immediate send local dispatch. I wrote directly in the browser; do not trust my brain compiler :laughing:

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