Riak
≈ 4 min read
Names in other languages
No names in other languages are held for this entry yet.
Article bodies are English and are not machine-translated. A name in another language is not a translation of the article.
Riak (pronounced "ree-ack" ) is a distributed NoSQL key-value data store that offers high availability, fault tolerance, operational simplicity, and scalability. Riak moved to an entirely open-source project in August 2017, with many of the licensed Enterprise Edition features being incorporated. Riak implements the principles from Amazon's Dynamo paper with heavy influence from the CAP theorem. Written in Erlang, Riak has fault-tolerant data replication and automatic data distribution across the cluster for performance and resilience. Riak has a pluggable backend for its core storage, with the default storage backend being Bitcask. LevelDB is also supported, with other options (such as the pure-Erlang Leveled) available depending on the version. Riak was originally developed by engineers employed by Basho Technologies and maintained by them until 2017 when the rights were sold to bet365 after Basho went into receivership.
Riak (pronounced "ree-ack" ) is a distributed NoSQL key-value data store that offers high availability, fault tolerance, operational simplicity, and scalability. Riak moved to an entirely open-source project in August 2017, with many of the licensed Enterprise Edition features being incorporated. Riak implements the principles from Amazon's Dynamo paper with heavy influence from the CAP theorem. Written in Erlang, Riak has fault-tolerant data replication and automatic data distribution across the cluster for performance and resilience. Riak has a pluggable backend for its core storage, with the default storage backend being Bitcask. LevelDB is also supported, with other options (such as the pure-Erlang Leveled) available depending on the version. Riak was originally developed by engineers employed by Basho Technologies and maintained by them until 2017 when the rights were sold to bet365 after Basho went into receivership.
Main features
Fault-tolerant availability: Riak replicates key/value stores across a cluster of nodes with a default n_val of three. In the case of node outages due to network partition or hardware failures, data can still be written to a neighboring node beyond the initial three, and read-back due to its "masterless" peer-to-peer architecture. Queries: Riak provides a REST-ful API through HTTP and Protocol Buffers for basic PUT, GET, POST, and DELETE functions. More complex queries are also possible, including secondary indexes, search (via Apache Solr), and MapReduce. MapReduce has native support for both JavaScript (using the SpiderMonkey runtime) and Erlang. Predictable latency: Riak distributes data across nodes with hashing and can provide latency profile, even in the case of multiple node failures. Storage options: Keys/values can be stored in memory, disk, or both. Multi-datacenter replication: Multi-Datacenter replication (MDC) provides uni-directional and bi-direction replication of data between Riak clusters, whether locally for resilience or globally for faster regional access. Uni-directional replication is useful for read-only sinks such as backups and Disaster Recovery sites. Bi-directional replication allows for multiple Riak cluster to have eventually consistent data across vast distances. Complex replication scenarios such as chains, hub-and-spoke and mesh networks are possible due to the Cascades feature, which allows replication of data between clusters that are not directly connected. There are two primary modes of operation: fullsync and realtime. Fullsync mode ensures that all data on the source cluster is replicated to the sink cluster. Only the metadata and changes are transferred, making this fast and efficient. Realtime mode sends updates made to a source cluster to the sink cluster in realtime. These modes are designed to work together for best performance All multi-datacenter replication occurs over multiple concurrent TCP connections to maximize performance and network utilization. Tunable consistency: Option to choose between eventual and strong consistency for each bucket.
Language support
Riak has official drivers for Ruby, Java, Erlang and Python. There are also numerous community-supported drivers for other programming languages.
Users
Notable users include AT&T, Comcast, GitHub, Best Buy, UK National Health Services (NHS), The Weather Channel, and Riot Games.
See also
Basho Technologies Apache Accumulo Oracle NoSQL Database NoSQL Structured storage Memcached Redis
References
External links
Text derived from https://en.wikipedia.org/w/index.php?oldid=1333971044 under CC BY-SA 4.0; modifications have been made.