[BEAM-14464] Optimize precombining table.

• Type: Improvement
• Status: Open
• Priority: P2
• Resolution: Unresolved
• Component/s: sdk-java-core
• Assignee: Unassigned
• Reporter: Robert Bradshaw
• Created: 12/May/22 17:20
• Updated: 05/Jun/22 01:14

Description

The current code constructs, hashes, and compares full WindowedValues for the grouping key, which ends up dominating the time spent in the combining table when using trivial combiners (like Sum.integers()). We only need compare the (structural value of the) key and windows, and can emit the windows in the global case.

Issue Links

• links to: GitHub Pull Request #17641