How do Vector Clocks work?

The vector clock algorithm defines the order between two events whenever inter-process communication creates a causal link between the two events. By tracking the logical clock of each process in the system, we make it possible compare and form a globally consistent snapshot of system state.

What are the advantages of vector clock?

Advantages of vector clock: Vector Clocks are used in distributed systems to determine whether pairs of events are causally correlated. Using Vector Clocks, timestamps are created for each event in the system, and their fundamental relationship is determined by comparing those timestamps.

Is vector clock a logical clock?

Like Lamport’s Clock, Vector Clock is also a logical clock, which is used to assign timestamps for events in a distributed system. Vector clock also gives a partial ordering of the events.

What is the advantage of vector clock over Lamport clock?

Vector Clocks represent an extension of Lamport Timestamps in that they guarantee the strong clock consistency condition which (additionally to the clock consistency condition) dictates that if one event’s clock comes before another’s, then that event comes before the other, i.e., it is a two-way condition.

What are the purposes of using vector clocks in distributed systems?

To sum up, Vector clocks algorithms are used in distributed systems to provide a causally consistent ordering of events but the entire Vector is sent to each process for every message sent, in order to keep the vector clocks in sync.

How do we synchronize physical clocks?

The clock synchronization can be achieved by 2 ways: External and Internal Clock Synchronization. External clock synchronization is the one in which an external reference clock is present. It is used as a reference and the nodes in the system can set and adjust their time accordingly.

What are the purposes of using Vector Clocks in distributed systems?

What are different types of clock in distributed system?

There are 2 types of clock synchronization algorithms: Centralized and Distributed. Centralized is the one in which a time server is used as a reference. The single time server propagates its time to the nodes and all the nodes adjust the time accordingly.

Why do we use logical clocks?

A logical clock is a mechanism for capturing chronological and causal relationships in a distributed system. Distributed systems may have no physically synchronous global clock, so a logical clock allows global ordering on events from different processes in such systems.

What is the problem with Lamport clocks that Vector Clocks solve?

The problem with Lamport Timestamps is that they can’t tell if events are concurrent or not. This problem is solved by Vector Clocks.

What are the limitations of Lamport’s logical clock?

Limitations of Lamport’s Logical Clocks Lamport’s logical clocks lead to a situation where all events in a distributed system are totally ordered. That is, if -> , then we can say C ( a ) < C ( b ) . Unfortunately, with Lamport’s clocks, nothing can be said about the actual time of a and b.

What are clocks in distributed system?