centra
8f94aee1fa
- Remove gitlinks (160000 mode) for chainfire, flaredb, iam - Add workspace contents as regular tracked files - Update flake.nix to use simple paths instead of builtins.fetchGit This resolves the nix build failure where submodule directories appeared empty in the nix store. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
45 lines
1.4 KiB
Markdown
45 lines
1.4 KiB
Markdown
# Data Model: Multi-Raft (Static → Split → Move)
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## Entities
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- **Store**
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- `id: u64`
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- `addr: String`
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- Holds multiple `Peer` instances (one per `Region` replica) and reports status to PD.
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- **Region**
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- `id: u64`
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- `start_key: bytes`
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- `end_key: bytes` (empty = infinity)
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- `voters: Vec<u64>` (store IDs)
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- `leader_id: u64`
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- `approx_size_bytes: u64`
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- **Peer**
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- `store_id: u64`
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- `region_id: u64`
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- `raft_state: HardState, ConfState`
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- `pending_eventual: VecDeque<(ns_id, key, value, ts)>`
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- **Placement Metadata (PD)**
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- `stores: [Store]`
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- `regions: [Region]`
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- `move_directives: [(region_id, from_store, to_store)]`
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## Relationships
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- Store 1..* Peer (per Region replica)
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- Region 1..* Peer (across Stores)
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- PD owns canonical Region→Store mapping and Move directives.
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## Lifecycle
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- **Bootstrap**: PD returns initial `regions` → Store creates Peers and persists meta.
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- **Split**: Region exceeds threshold → Split command commits → two Region metas persisted → new Peer created.
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- **Move**: PD issues `MoveRegion` → leader adds replica on target store (ConfChange Add) → replica catches up → old replica can be removed via ConfChange Remove.
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## Constraints
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- Region key ranges must be non-overlapping and sorted.
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- Raft storage/logs are prefixed by `region_id` to avoid cross-region collisions.
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- Quorum required for writes; ConfChange operations must preserve quorum at each step.
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