How does a vector clock detect concurrent events?
A vector clock is a counter for each node in the cluster. Two events are concurrent if neither event's vector is less-than-or-equal (elementwise) to the other. This means no message passed between them, so neither caused the other—a genuine conflict requiring resolution, not silent data loss.
Answered in
Vector Clocks: Detecting Causality in Distributed SystemsVector clocks solve distributed ordering: when wall-clock timestamps fail to detect concurrent writes, vector clocks reveal true causality and conflicts.
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