GFS Consistency Model
Explore the Google File System consistency model focusing on how file regions behave after mutations. Learn the definitions of consistency states, the role of record appends, and ways applications adapt to GFS's relaxed consistency model for reliable distributed file management.
GFS provides a custom consistency model for write operations.
The state of a file region after a mutation depends on the type of mutation, whether it succeeds or fails and whether there are concurrent mutations.
Note: A file region is consistent if all clients will always see the same data, regardless of the replica they read from.
A region within a file
A region is defined after a file data mutation if it is consistent and clients will see what the mutation writes in its entirety.
A region can be:
- Defined and consistent: When a mutation succeeds without interference from concurrent writes, the affected region is defined. All clients will always see what the mutation