Hi @Stefan ,
Thanks for reaching out to Q&A.
Concurrency would definitely help in improving the performance and throughput however you would like to have only one receiver. I would suggest you to make use of the prefetch feature in service bus. Prefetch speeds up the message flow by having a message readily available for local retrieval before the application asks for one. When you enable the Prefetch feature for any of the official Service Bus clients, the receiver acquires more messages than what the application initially asked for, up to the specified prefetch count.
Please note that, prefetch is not enabled by default. To enable the Prefetch feature, set the prefetch count of the queue or subscription client to a number greater than zero. Setting the value to zero turns off prefetch. Please try this and let me know if the throughput is increased.
I hope this helps! Feel free to reach out to me if you have any queries or concerns.
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