In a distributed system such as a distributed shared memory system or a distributed data store such as a database, filesystem, or web caching system, there are a number of possible data consistency models. System supports a given model if operations on memory follow specific rules. Essentially it's a deal between programmer and system, when system guarantees, that if programmer will follow some rules, memory will be consistent and results of the memory operations will be predictable.
Examples include:
- strict consistency
- sequential consistency
- eventual consistency
- delta consistency
- linearizability
- PRAM consistency
- weak consistency
