Spring cloud stream - concurrency

General Discussions
1

Hi there
I’m trying to configure more than one Consumer Thread for my functional consumer
But I saw that when I config concurrency as 5. It will create 5 session connection to the solace server.
when config concurrency is 5. It will create 5 session connection to the solace
when config concurrency is 10. It will create 10 session connection to the solace
is it the bug?

2

Hi @tuancris92 ,
It is not a bug. The concurrency setting is meant for creating concurrent consumer flows to consume messages from the queue. Note that the group’s queue must have been non-exclusive (default if not specified) - that’s how it supports multiple consumers on the queue. More info can be found in the Spring Cloud Stream binder docs .
If you want to create multiple consumers connecting to the same queue, consider multiple instances of the same application with a single consumer session.
[EDIT] Concurrency implies the number of flows created in a session - not concurrent session.

3

Hi @giri , Thank you for your answer. Do you have any problem if have a lot of session connections to the solace server?

4

No, it is something configurable on the queue. Using CLI or Solace Broker manager, you can set this limit on the queue.

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5

But if have a lot of connection sessions to solace MQ, do they make the solace MQ slow? Do we have a document talk about this? @giri

6

Solace queue supports up to 10000 with a default of 1000 consumer flows per queue.
I would also recommend reading this thread that goes into this and related topics Parallel processing of messages by Solace — Solace Community
And a blog on consumer scaling https://solace.com/blog/consumer-groups-consumer-scaling-solace/
Note that the topic we are discussing is general Solace Queue consumers and scaling - this applies to Solace queue access via any APIs and frameworks.