Patterns of Distributed Systems

Chapter 24

Clock-Bound Wait

Wait to cover the uncertainty in time across cluster nodes before reading and writing values so that values can be correctly ordered across cluster nodes.

Problem

Both Alice and Bob can ask server Green for the latest version timestamp of the key they are trying to read. But that requires one extra round.

If Alice and Bob are trying to read multiple keys across a set of servers, they will need to ask the latest version for each and pick the maximum value.

Consider a key-value store where values are stored with a timestamp to designate each version. Any cluster node that handles a client request will be able to read the latest version using the current timestamp at the request processing node.

In Figure 24.1, the ...