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Solution: If we change the ordering of messages in a batch to prefix with headers of all messages first and followed by the payload of all messages, it will lead to an optimization where we have to "partially" decompress the batch (i.e. the prefix).

Ideas for message format v.3 wiki: ideas for kafka message format v.3

Motivation

Logs in kafka consists of batches, and one batch consists of many messages. So if the size of each message header can be reduced, it'll improve the network traffic and storage size (and money, of course) a lot, even it's a small improvement. Some companies now handle trillions of messages per day using Kafka, so, if we can reduce just 1 byte per message, the save is really considerable.

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