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• Add a CreateTime field to ProducerRecord. This field can be used by application to set the send time. It will also allow mirror maker to maintain the send time easily.
• Add both CreateTime and LogAppendTime to ConsumerRecord.
  • The CreateTime is useful in use cases such as stream processing
  • The LogAppendTime is useful in use cases such as log rolling and log retention.

Option 2 -

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Add only LogAppendTime to the message

See Rejected Option Section

Option 3 -

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Add only CreateTime to the message

While the time based log index has to be based on LogAppendTime, there is some concern about exposing the LogAppendTime (which is a broker internal concept) to user. And there will also be some per message overhead for two timestamps.

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During step 2 and step 3, the majority of the consumers may be still using consumers using MessageAndOffset V0, broker could consume more memory.

Rejected Alternatives

Option 2 - Adding only LogAppendTime to the message

This proposal is pretty much the same as the selected proposal, except it does not include CreateTime in the message format.

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