Add sharded transaction manager for multi-Raft support #224
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Summary of Changes
Hello @bootjp, I'm Gemini Code Assist1! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!
This pull request introduces a ShardedTransactionManager to provide robust multi-Raft support, allowing the system to distribute and manage transactions across various Raft consensus groups. This enhancement is crucial for scaling the key-value store by sharding data and operations, ensuring that requests are efficiently routed to the correct shard for processing.
Highlights
- Introduction of ShardedTransactionManager: A new component designed to route transaction requests to different Raft groups based on key distribution.
- Multi-Raft Support: This manager enables the system to handle transactions across multiple independent Raft consensus groups, facilitating sharding.
- Comprehensive Testing: New tests have been added to verify the correct routing and commitment of requests across separate Raft groups.
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Code Review
This pull request introduces a ShardedTransactionManager to handle requests across multiple Raft groups. The implementation correctly routes requests based on key ranges. However, there are some critical areas for improvement. The most significant issue is that the Commit method does not provide atomicity across shards, which can lead to data inconsistency in case of partial failures. I've recommended implementing a two-phase commit (2PC) protocol to address this. Additionally, I've pointed out code duplication between the Commit and Abort methods and suggested a refactoring. Finally, I've recommended enhancing the tests to cover failure scenarios to ensure the system's robustness.
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| // helper to create a multi-node raft cluster and return the leader | ||
| func newTestRaft(t *testing.T, id string, fsm raft.FSM) (*raft.Raft, func()) { |
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🚫 [golangci] reported by reviewdog 🐶
calculated cyclomatic complexity for function newTestRaft is 14, max is 10 (cyclop)
Summary
ShardedTransactionManagerto route requests to raft groups using distribution engineTesting
go test ./...golangci-lint run ./...(fails: can't load config: the Go language version (go1.24) used to build golangci-lint is lower than the targeted Go version (1.25.0))https://chatgpt.com/codex/tasks/task_e_68b1f48d88188324ba20fe70179ff57e