A logical clock is a mechanism for capturing chronological and causal relationships in a distributed system.
Logical clock algorithms of note are:
- Lamport timestamps, which are monotonically increasing software counters.
- Vector clocks, that allow for total ordering of events in a distributed system.
- Version vectors, order replicas, according to updates, in an optimistic replicated system.
- Matrix clocks, an extension of vector clocks that also contains information about other processes' views of the system.
Famous quotes containing the words logical and/or clock:
“It is possible—indeed possible even according to the old conception of logic—to give in advance a description of all ‘true’ logical propositions. Hence there can never be surprises in logic.”
—Ludwig Wittgenstein (1889–1951)
“The clock of communism has stopped striking. But its concrete building has not yet come crashing down. For that reason, instead of freeing ourselves, we must try to save ourselves from being crushed by its rubble.”
—Alexander Solzhenitsyn (b. 1918)