Vector clock.
also: vector clocks · version vector · version vectorsA map of per-node counters attached to data that shows whether one version happened before another or both are concurrent.
the two-minute refresher
- Each node increments its own counter on a write and sends the whole vector along.
- V1 < V2 if every entry ≤ and at least one <: V1 happened before.
- {A:1, B:2} vs {A:2, B:1}: neither dominates, so they are concurrent, a real conflict.
- Detects conflicts; the application (or a CRDT) still decides how to merge.