[KAFKA-5186] Avoid expensive initialization of producer state when upgrading

• Type: Sub-task
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Fix Version/s: 0.11.0.0
• Component/s: clients, core, producer
• Labels: exactly-once
• Assignee: Jason Gustafson
• Reporter: Jason Gustafson
• Created: 07/May/17 22:05
• Updated: 22/May/17 22:43
• Resolved: 22/May/17 22:43

Description

Currently the producer state is always loaded upon broker initialization. If we don't find a snapshot file to load from, then we scan the log segments from the beginning to rebuild the state. Of course, when users upgrade to the new version, there will be no snapshot file, so the upgrade could be quite intensive. It would be nice to avoid this by assuming instead that the absence of a snapshot file means that the producer state should start clean and we can avoid the expensive scanning.

Issue Links

• links to: GitHub Pull Request #3113