SAVESynchronously snapshot the dataset to disk.
| Syntax | SAVE |
| Group | server |
| Arity | 1 |
| Since | 1.0.0 |
| Flags | write, admin |
| Complexity | O(S) fan-out; O(N/S) copy-on-write freeze per shard |
| Redis compatibility | differs: SAVE is no longer synchronous-until-durable — it freezes a copy-on-write view and replies OK immediately, so 'SAVE returned, therefore the dump is safe to copy' no longer holds |