[KAFKA-5285] Optimize upper / lower byte range for key range scan on windowed stores

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: streams
• Labels: performance
• Assignee: Guozhang Wang
• Reporter: Xavier Léauté
• Created: 19/May/17 00:20
• Updated: 09/Feb/21 03:33

Description

The current implementation of WindowKeySchema / SessionKeySchema upperRange and lowerRange does not make any assumptions with respect to the other key bound (e.g. the upper byte bound does not depends on lower key bound).

It should be possible to optimize the byte range somewhat further using the information provided by the lower bound.

More specifically, by incorporating that information, we should be able to eliminate the corresponding upperRangeFixedSize and lowerRangeFixedSize, since the result should be the same if we implement that optimization.

Issue Links

• incorporates: KAFKA-4608 RocksDBWindowStore.fetch() is inefficient for large ranges
• relates to: KAFKA-12314 Leverage custom comparator for optimized range scans on RocksDB
• links to: GitHub Pull Request #4576