monotonic-writes · shipping · also Monotonic-write consistency, MW session guarantee

Monotonic writes

Monotonic writes requires every replica incorporating a later session write to incorporate the session's earlier writes and order them before it.

Related Observatory article: Monotonic writes on hesela.com

This is write ordering, not increasing numeric values. MongoDB's causal-session documentation allows unrelated writes to interleave; one thread must use the session at a time. Its documented majority read and write concerns provide all four causal guarantees with durability; weaker configurations require separate analysis.

Relations

related

session-guarantees, writes-follow-reads

Citations

1. Douglas B. Terry et al. Session Guarantees for Weakly Consistent Replicated Data. PDIS 1994, sections 3.1-3.4, pp. 142-144. (accessed 2026-10-13)
2. MongoDB Manual: Read Isolation, Consistency, and Recency; client sessions, causal guarantees and isolation. (accessed 2026-10-13)
3. Storage consistency: ordering is not a transaction or a durability promise (accessed 2026-10-13)
4. MongoDB Manual: Causal Consistency and Read and Write Concerns; durability and rollback distinctions. (accessed 2026-10-13)

JSON: /data/terms/monotonic-writes.json