Meskipun Redis adalah in-memory, Redis dapat mempertahankan data ke disk sehingga data bertahan setelah restart. Redis menawarkan dua mekanisme — RDB (snapshot point-in-time) dan AOF (append-only log operasi) — dengan trade-off durabilitas/performa yang berbeda.
RDB — snapshot point-in-time
RDB takes SNAPSHOTS of the dataset at intervals, saving a compact binary file.
✓ Compact single-file backups; fast restarts (load the snapshot)
✓ Good for backups and disaster recovery; less impact on performance
✗ You can LOSE data since the last snapshot (e.g. last few minutes) if Redis crashes
→ Configure save points: e.g. "save after 900s if ≥1 change, 300s if ≥10 changes"
