[CASSANDRA-15387] Reduce compaction & local read path garbage

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 4.0.x
• Component/s: Local/Compaction
• Change Category: Performance
• Complexity: Normal
• Platform: All
• Assignee: Blake Eggleston
• Reporter: Blake Eggleston

Authors

Blake Eggleston

• Created: 30/Oct/19 22:28
• Updated: 10/Oct/20 00:05
• Resolved: 06/Oct/20 22:58

Description

There are several opportunities to significantly reduce the amount of garbage generated by compaction and the local read path. This will serve as a top level jira for related changes.

Sub-Tasks

• Add compaction allocation measurement test to support compaction gc optimization.: Resolved
• Minimize BTree iterator allocations: Resolved
• Avoid unnecessary collection/iterator allocations during btree construction: Resolved
• Reduce heap footprint of commonly allocated objects: Resolved
• Pool Merge Iterators: Resolved
• Add byte array backed cells: Resolved
• Remove list iterators: Resolved
• Add compaction-related JMH tests: Patch Available