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Current state: "Under Discussion"

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

JIRA: here

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

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Which thread should be responsible for waiting?

*Default to Common Pool, Allow User Overrides

By default, we will use a common threadpool (either one managed by Kafka, or by the JDK (like FJP.commonpool)).  However, it will be possible for a user to override the pool.

Pros:

1. Easy to implement
2. Users have fine-grained control if they want, or they can relax and trust us

Cons:

1. Breaking API change, if only for the user override.

User-provided Threadpool

Update the API so that the user provides a threadpool, in which we do the blocking.

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Rejected Alternatives

Prior Art: KIP-286

Everything is on the table!  We can add things here as we reject them.