Definition - What does Eventual Consistency mean?
Eventual consistency is an aspect of the Basically Available, Soft State, Eventual Consistency (BASE) model of data operation design. The BASE model helps to promote different kinds of alternatives for the expansion or improved performance of database operations and similar systems by allowing for a more flexible protocol for matching data.
Techopedia explains Eventual Consistency
Generally, the BASE model for database operations is contrasted to another model called ACID, which prizes data consistency and guarantees that data will be updated and matched immediately within a system. BASE, on the other hand, allows for less rigid types of updates and data resolutions throughout the system, allowing some lag times that cause data mismatches. Eventual consistency is the idea that in a database or system using BASE philosophy, all of the data will eventually become consistent over time.
One way to think about eventual consistency is that instead of requiring immediate updates to a system, this model sets a fixed timeline for complete resolution within the system. That said, a design using eventual consistency must work to address data mismatches or inconsistencies as they occur. This requires various strategies for conflict resolution within the data infrastructure.