...

This page is meant as a template for writing a KIP. To create a KIP choose Tools->Copy on this page and modify with your content and replace the heading with the next KIP number and a description of your issue. Replace anything in italics with your own description.

Status

Current state:   [One of "Under Discussion", "Accepted", "Rejected"]

Discussion thread: here [Change the link from the KIP proposal email archive to your own email thread]

...

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

Motivation

...

When aggregating a KTable we need to repartition the messages by aggregation key to make all of them be processed by the same Task. Instead of using Change<V> serialized into an uncompacted topic we can publish the events into a compacted topic as they are and use the aggregation key to decide on the partition. This has some benefits users might find very helpful.

1.  small tables with many update can be much smaller in the repartition topics.
2. debugging repartitioned topics becomes easier because its not required to unserialize a Change<V> but only V itsself
3. One can finally present the aggregator with the key of the record that has to be added or removed from the aggregate

Public Interfaces

Briefly list any new interfaces that will be introduced as part of this proposal or any existing interfaces that will be removed or changed. The purpose of this section is to concisely call out the public contract that will come along with this feature.

...