[CASSANDRA-18485] CEP-15: (C*) Enhance in-memory FileSystem to work with mmap and support tests to add custom logic

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 5.0-alpha1, 5.0
• Component/s: Accord, Test/dtest/java, Test/unit
• Change Category: Quality Assurance
• Complexity: Normal
• Platform: All

Source Control Link

https://github.com/apache/cassandra/commit/4759a7353fca1dad330e913e7eaf1313890a35be

Test and Documentation Plan

existing tests

• Assignee: David Capwell
• Reporter: David Capwell

Authors

David Capwell

Reviewers

Caleb Rackliffe

• Created: 27/Apr/23 22:10
• Updated: 12/Sep/23 13:03
• Resolved: 08/May/23 23:11

Description

The Simulator currently uses JimFS for its FileSystem, but this lacks any way to add custom logic when file operations are performed; it also lacks mmap support which requires all disk access logic to provide non-mmap solutions as well.

As part of the Simulator work, testing disk corruption will require resolving both these issues, so will need a new FileSystem to rule them all…

This ticket is to define the new FileSystem and add the integration to Simulator, JVM-Dtest, and Unit tests, but does not directly add the fault injections that Simulator will be doing, that will be follow up work.

Goals:

• FileSystem that works for unit, jvm-dtest, and simulator tests
• FileSystem that allows tests to intercept file operations

Issue Links

• links to: CI: trunk
• links to: GH: trunk
• links to: GitHub Pull Request #2299