[LUCENE-10170] Regression in stored fields compression in 9.0

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 9.0
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Adrien Grand
• Created: 13/Oct/21 07:56
• Updated: 28/Aug/22 16:28
• Resolved: 14/Oct/21 06:50

Description

One of the Elasticsearch benchmarks detected a regression that is attributed to stored fields compression after moving to a 9.0 snapshot. I managed to isolate it to the change done on LUCENE-7521. It looks like LZ4 relied significantly on Direct16 for good performance, so replacing it with Packed64 degraded compression speed.

Issue Links

• links to: GitHub Pull Request #377