miroir/crates
jedarden 690cefe04e P4.2 Node addition: dual-write + paginated shard migration
Implement plan §2 "Adding a node to an existing group":

1. Admin API endpoints now use Rebalancer methods:
   - POST /_miroir/nodes → Rebalancer.add_node()
   - POST /_miroir/nodes/{id}/drain → Rebalancer.drain_node()
   - DELETE /_miroir/nodes/{id} → Rebalancer.remove_node()

2. Node addition flow:
   - Mark node as `joining`
   - Recompute assignments → affected_shards where new node enters top-RF
   - Dual-write: writes go to both old owner and new node
   - Background migration via _miroir_shard filter (paginated)
   - Mark `active`; stop dual-write
   - Delete migrated shard from old node

3. Integration tests (p42_node_addition.rs):
   - 3→4 node migration with 10K docs
   - Chaos: writes during migration caught by dual-write
   - Performance: ≤ total_docs/(Ng+1) × 1.1 docs moved
   - Log inspection: old node not queried after migration
   - Pagination verification with limit/offset
   - Dual-write verification

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
2026-05-08 15:15:35 -04:00
..
miroir-core P4.2 Node addition: dual-write + paginated shard migration 2026-05-08 15:15:35 -04:00
miroir-ctl P3: Phase 3 Task Registry + Persistence — COMPLETE 2026-05-02 16:50:42 -04:00
miroir-proxy P4.2 Node addition: dual-write + paginated shard migration 2026-05-08 15:15:35 -04:00