Concept
Sagas
Definition
A multi-step business transaction of local commits plus compensations, used when two-phase commit would hold locks across services.
Studies
- Sagas & Distributed Transactions — Orchestration, Choreography & CompensationsInterview hub on sagas versus 2PC, orchestration versus choreography, compensations, deadlines, and reconciliation for multi-service business transactions.
- Two-Phase Commit vs Sagas — Why 2PC Breaks at ScaleWhy 2PC blocks at scale, how that compares with sagas, and when a shared-database ACID transaction still wins.
- Orchestration vs Choreography — Central Coordinator vs Event DanceCentral coordinator versus an event dance for sagas, with decision guidance and pointers to outbox, inbox, and deadlines.
- Compensating Transactions — Idempotent Undo & Semantic RollbackIdempotent semantic undo for sagas: reverse-order compensations, void versus refund, and reversing ledger entries.
- Saga State Machines — Timeouts, Retries & DeadlinesSaga state machines with per-step timers, whole-saga deadlines, bounded retries, and durable state.
- Saga Failure Modes — Poison Steps, Partial Failure & ReconciliationPoison steps, partial failure, dead-letter quarantine, and idempotent reconciliation for sagas that miss their SLA.