[CASSANDRA-19482] Simplify metadata log implementation using custom partitioner

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 5.1-alpha1
• Component/s: Transactional Cluster Metadata
• Epic Link: CEP-21: Follow Up
• Change Category: Code Clarity
• Complexity: Normal
• Platform: All

Source Control Link

https://github.com/apache/cassandra/commit/728b9ec4c604f6939facf62a261ca795ef6dbf0c

Test and Documentation Plan

New and existing tests in attached CI results.
The few failures/errors in the attached results are known (CASSANDRA-19343) or look to be infra-related.

• Assignee: Sam Tunnicliffe
• Reporter: Sam Tunnicliffe

Authors

Marcus Eriksson, Sam Tunnicliffe

Reviewers

Alex Petrov

• Created: 20/Mar/24 14:26
• Updated: 07/Jun/24 14:08
• Resolved: 11/Apr/24 08:09

Description

The distributed metadata log table can be simplified by leveraging the fact that replicas are all responsible for the entire token range. Given this assumption, we can then use ReversedLongLocalPartitioner introduced in CASSANDRA-19391 to make it much easier to append to/read from the tail of the log, effectively removing the need for the Period construct. This will also improve apply to the local metadata log used at startup.

Issue Links

• is related to: CASSANDRA-19692 ClassCastException on selection with where clause from system.local_metadata_log
• links to: GitHub Pull Request #3197