Docs: Kafka backend default configuration

[FabioGentile]

Is your documentation request related to a feature? If so, which one?

Kafka backend configuration

What is the solution that you would like or the expected outcome?

This page currently says that no additional configuration is needed if using Apache or Confluent Kafka. I think this might be incorrect, as the ingest-storage.kafka.producer-max-record-size-bytes config has a default value of 15MB, while Kafka message.max.bytes usually defaults to 1MB (see Confluent and Apache docs).

This is not a problem with Warpstream as their default message.max.bytes is 64000000 bytes.

What did you think would happen?

While not a big problem on it's own, having a message.max.bytes < ingest-storage.kafka.producer-max-record-size-bytes could cause some messages to be discarded by Kafka.

What was your environment?

Mimir 3.0.1

Any additional context to share?

I'm not familiar with Kafka and we have just started experimenting with the new ingest storage architecture, so my understanding of these settings might be wrong.

Alternatively, instead of changing the message.max.bytes setting on Kafka side, it's also possible to reduce the Mimir ingest-storage.kafka.producer-max-record-size-bytes value to 1MB, but that config description says

We strongly recommend to not change this setting unless for testing purposes.

So i'm not sure if it's a viable option