Saga Message Handlers multiple instances

[ghost]

Hey @mizrael, great software you got here. Thank you for sharing.

I'm not sure if I missed a setting or if it's not possible, but I tested around with a simple setup (local/console app/InMemoryTransport) the handling of multiple requests. It seems that each message handler can only run one instance simultaneously.

My Saga contains three message handlers that follow each other up, all got Task delays to keep it busy. When sending three requests message handler 1 runs request 1. After message handler 1 is done with request 1, only then it starts with request 2.
It does support different message handlers to work simultaneously; so when handler 1 is working on request 2, handler 2 starts with request 1.

Is there support for multiple instances per handler?

Thanks!

[mizrael]

hi @MarijnBlue10, thanks for reaching out! Would you be able to push your code to a repo so that I can replicate the issue?

thanks!

[mizrael]

nevermind, I think I got the issue. the InMemorySubscriber is processing messages one after the other. I'll change that in the next release, it'd be more similar to what the real subscribers are doing.

thanks for pointing this out!

[ghost]

Ah the problem is in the InMemory part. Thanks for the quick reply :).
I'm looking forward to the new release

[ghost]

@mizrael, I had the same problem while using AzureServiceBus. Apparently the ServiceBusClient.CreateProcess has the option MaxConcurrentCalls that by default is 1. Changing the option like below solves the issue:

var options = new ServiceBusProcessorOptions
{
      MaxConcurrentCalls = 20
};
 _processor = serviceBusClient.CreateProcessor(references.TopicName, references.SubscriptionName, options);

[mizrael]

thanks for pointing this out! I'll add it to the next release :)

[mizrael]

hi @MarijnBlue10 , can you please check https://github.com/mizrael/OpenSleigh/releases/tag/v2.0.2 and let me know if solves your issue?

[ghost]

I checked v2.0.3 and it works good :D.
AzureServiceBus works like a charm and I love the configuration setting. Great job.
InMemoryTransport works fine. Each handler now starts multiple requests. which is great. The minor difference is that it still waits till the batch of requests is finished before starting the next batch.

I will be sticking with AzureServiceBus so I'm all good. Thanks a lot.

[mizrael]

glad it helped! Yes, the batch processing is intentional. Setting to 1 would mean sequential processing (like it was before). Setting to a very high value it's likely to cause resource starvation. You just need to tune it based on your infrastructure and messaging requirements :)