Correct Number of Partitions/Replicas for @RetryableTopic Retry Topics

Hello Stack Overflow community and anyone familiar with spring-kafka!

I am currently working on a project which leverages the @RetryableTopic feature from spring-kafka in order to reattempt the delivery of failed messages. The listener annotated with @RetryableTopic is consuming from a topic that has 50 partitions and 3 replicas. When the app is receiving a lot of traffic, it could possibly be autoscaled up to 50 instances of the app (consumers) grabbing from those partitions. I read in the spring-kafka documentation that by default, the retry topics that @RetryableTopic autocreates are created with one partition and one replica, but you can change these values with autoCreateTopicsWith() in the configuration. From this, I have a few questions:

• With the autoscaling in mind, is it recommended to just create the retry topics with the same number of partitions and replicas (50 & 3) as the original topic?
• Is there some benefit to having differing numbers of partitions/replicas for the retry topics considering their default values are just one?

The retry topics should have at least as many partitions as the original (by default, records are sent to the same partition); otherwise you have to customize the destination resolution to avoid the warning log. See Destination resolver returned non-existent partition

50 partitions might be overkill unless you get a lot of retried records.

It's up to you how many replicas you want, but in general, yes, I would use the same number of replicas as the original.

Only you can decide what are the "correct" numbers.