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For the first partition, server always fetches at least least one message.max. bytes. Empty response limits will be returned for all partitions that didn't fit into response limit.

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• FetchRequest with response_max_bytes != Int.MAX_INT always makes progress - if server has message(s), than at least one message is returned irrespective of response_max_bytes
• FetchRequest response size will not be bigger than max(response_max_bytes, message.max.bytessize of the first message in first partition)

Since new fetch request processes partitions in order and stops fetching data when response limit is hit, client should use some kind of partition shuffling to ensure fairness.

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