Consistency

Consistency has been introduced to Dynomite in version 0.5.0 in the local region. There are two configurations.

DC_ONE: Reads and writes are propagated synchronously only to the node in the local Rack (Availability Zone) and asynchronously replicated to other Racks and regions.

DC_QUORUM: Reads and writes are propagated synchronously to quorum number of nodes in the local region and asynchronously to the rest.

Consistency can be configured for read or write operations separately (clusterwide). Adding consistency can be done through the stats port (default 22222):

curl http://localhost:22222/set_consistency/read/dc_quorum

curl http://localhost:22222/set_consistency/write/dc_quorum

To check the node level consistency:

curl "http://localhost:22222/get_consistency"

For example the output can be

Read Consistency: DC_ONE
Write Consistency: DC_ONE