Vector Clocks

Kind: mechanism

Layer: Causality Core

Record: architecture:vector-clocks

Severity: contextual

Scope: distributed events, replication

Canonical: Ontology

A mechanism that keeps one counter per node on each update, so two updates can be compared as ordered or concurrent.

Listed in Architecture principles, after Directed Acyclic Graph (DAG) and before Lamport Clocks.

Requires

• Node Identity
• Version Vector

Reinforces

• Causal Consistency

Enables

• Concurrent Update Detection

Conflicts with

• Single Global Clock Assumption

In tension with

• Metadata Size

Tensions

• Vector Clocks / Metadata Size

Violated by

• Lost Update

Severity

• contextual

Category

• Causality / Ordering / Distributed Time

Linked from

• Execution joins the halves
• Causality / Ordering / Distributed Time
• Causality / Ordering / Distributed Time
• Severity levels
• The resolutions