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 merely a linguistic peculiarity, not a logical fact, that we say “that is red” instead of “that reddens,” either in the sense of growing, becoming, red, or in the sense of making something else red.”
—John Dewey (1859–1952)
“What brought them there so far from their home,
Cuchulain that fought night long with the foam,
What says the Clock in the Great Clock Tower?
Niamh that rode on it; lad and lass
That sat so still and played at the chess?
What but heroic wantonness?”
—William Butler Yeats (1865–1939)