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:
“Opera, next to Gothic architecture, is one of the strangest inventions of Western man. It could not have been foreseen by any logical process.”
—Kenneth MacKenzie Clark, Baron of Saltwood (1903–1983)
““Pop” Wyman ruled here with a firm but gentle hand; no drunken man was ever served at the bar; no married man was allowed to play at the tables; across the face of the large clock was written “Please Don’t Swear,” and over the orchestra appeared the gentle admonition, “Don’t Shoot the Pianist—He’s Doing His Damndest.””
—Administration in the State of Colo, U.S. public relief program. Colorado: A Guide to the Highest State (The WPA Guide to Colorado)