Appendix D — Glossary and Commonly Confused Boundaries
| Term | Meaning in this book | Do not conflate with |
|---|---|---|
| DSM | distributed shared-memory foundation for repairable coordination state | distributed-database replacement |
| Runtime | DsmRuntime owning identity, registry, lifecycle, and
collaboration components |
the JVM process itself |
| locator | tenantId / applicationId / collectionId |
collection name alone |
| Register | current visible value per key with deterministic convergence | linearizable KV |
| Lease | time-bounded ownership, mode, and fencing token | distributed transactional lock |
| CRDT | mergeable state with commutative, associative, idempotent merge | arbitrary business data made correct automatically |
| local commit | local path accepts and updates projection | visibility on every peer |
| live delta | normal online propagation path | synchronous strong replication |
| repair | replay/snapshot of current replica state after digest | complete business-history replay |
| convergence | equivalent visible state after recovery | only one success during partition |
| membership | members and states observed by this node | instantaneous global truth |
| fencing token | monotonic token used by an external resource to reject an old owner | DSM blocking every external write automatically |
| ChangeStream | bounded state-change observation stream | lossless audit log |
| diagnostics | immutable runtime snapshot from one node | authoritative business fact |
| Federation | collection-semantic propagation across clusters | global transaction or one cross-region Lease owner |
| E1–E4 | execution surfaces from static assets to real ports | quality score or production-maturity level |
Five key boundaries
putconfirms local commit; remote visibility needs separate evidence.- Repair restores convergence and does not revoke a returned OK.
- Lease supplies a token; the external resource validates it.
- A test proves assertions under a revision, environment, and topology, not production readiness automatically.
- Federation propagates collection semantics and does not create a cross-region transaction.
The complete editorial terminology standard is in the project glossary.