What does eventual consistency imply?

Eventual consistency is a consistency model used in distributed systems that allows for temporary inconsistencies while ensuring that, over time, all updates to data will be propagated and all nodes in the system will converge to the same state. In this context, the correct answer captures the essence of how eventual consistency operates.

When a change is made in a distributed system, it may not be immediately visible in all parts of the system due to synchronization delays. This means that different parts of the system might reflect different values temporarily. However, over time, changes made in one part of the system will be propagated to all locations, leading to a consistent state.

The idea that data changes may appear out of order refers to the fact that if changes occur simultaneously or are made at different times, the sequence in which they become visible can vary across different nodes. This behavior is fundamental to how eventual consistency operates, allowing for high availability and performance at the expense of immediate consistency.

In contrast, immediate visibility of data changes or the need for manual refresh would indicate stronger consistency models, such as strong consistency. Likewise, requiring all changes to be confirmed before visibility is typical of a strictly consistent model like linearizability. These aspects contrast with the flexibility that eventual consistency provides, where it priorit