[CASSANDRA-19675] Avoid streams in the common case for UpdateTransaction creation

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 5.0, 5.1
• Component/s: Feature/SAI
• Epic Link: Storage Attached Indexes (Phase 3)
• Change Category: Performance
• Complexity: Low Hanging Fruit
• Platform: All

Source Control Link

https://github.com/apache/cassandra/commit/ba5ab993c7a279b014f439a5d06683d3b568d4ff

Test and Documentation Plan

Diff is just converting a bunch of stream() usage to using loops. Not destabilizing existing tests should be sufficient.

• Assignee: Caleb Rackliffe
• Reporter: Caleb Rackliffe

Authors

Caleb Rackliffe

Reviewers

David Capwell, Jeremiah Jordan

• Created: 31/May/24 17:53
• Updated: 20/Jun/24 16:32
• Resolved: 20/Jun/24 16:32

Description

Some recent Accord profiling highlighted some easily addressable inefficiency in the way we create new UpdateTransaction objects in SecondaryIndexManager that have existed since the introduction of index groups for SAI. We should be able to clean this up by avoiding stream creation or even iteration over the groups when there is a single index group, which is going to be the most common case with SAI anyway. If we do have to iterate, there should also be no reason to copy the collection of index groups via listIndexGroups(), although that copying can remain in the method itself for external callers.

Issue Links

• is related to: CASSANDRA-19673 Investigate stream pipelines in hot paths
• links to: GitHub Pull Request #3370
• links to: GitHub Pull Request #3376