Riak
- HTTP API
- Master-less, so remains operational even if multiple nodes fail
- Near linear scalability
- Architecture same of both large and small clusters
- Key/value model, flat namespace, can store anything
Redis
- Key/value. Can store data types such as sets, sorted lists, hashes and do operations on them such as set intersection and incrementing the value in a hash.
- In-memory dataset
- Easy to setup, master/slave replication
Hibari
- Very simple data model with 5 attributes: keys, values, timestamps, expiry date, flags for metadata
- Chain replication across nodes that are geographically dispersed. Not single points of failure
- Excellent performance for large batches (~200k) read/write operations
- Runs on commodity hardware or blades. Does not require SAN
Hypertable
- High performance, massively scalable, modeled after Google’s Bigtable
- Runs on top of a distributed file system such as Apache Hadoop DFS, GlusterDS, or Kosmos File System
- Data model is a traditional, but huge table, that is physically stored in sort order of the primary key
Voldemort
- High scalability due to allowing only very simple key/value data access.
- Used by LinkedIn
- Not an object or a relational database. Just a big, distributed, fault-tolerant, persistent hash table
- Includes in-memory caching, so separate caching tier isn’t required
MemcacheDB
- High performance persistent storage that’s compatible with Memcache protocol
Tarantool
- NoSQL database with messaging server
- All data maintained in RAM. Persistence via a write ahead log.
- Asynchronous replication and hot standby
- Supports stored procedures
- Data model: tuples (unique key plus any number of other fields); spaces (multiple tuples)
Apache Cassandra
- Can use massive cluster of commodity servers with no single point of failure. Can be deploy across multiple data centers.
- Was used by Facebook for Inbox Search until 2010
- Read/write scales linearly with number of nodes
- Data replicated across multiple nodes
- Supports MapReduce, Pig, and Hive
- Has SQL-like CQL providing for a hybrid between key/value and tabular database
HyperDex
- NoSQL key/value that provides lower latency and higher throughput than some alternatives
- Replicates data to multiple nodes
- Very easy to administer and maintain
- Data model: key plus zero or more attributes
Lightcloud
- Great performance even on small clusters with millions of keys
- Nodes replicated via master-to-master replication. Hot backups and restores
- Very small client footprint
- Built on top of Tokyo Tyrant
Sources:
- http://www.toolsjournal.com/integrations-articles/item/1852-10-key-value-store-distributed-open-source-databases-for-your-bigdata-needs
- http://basho.com/riak/
- http://redis.io/
- https://github.com/hibari/hibari
- http://hypertable.com/
- http://www.project-voldemort.com/voldemort/
- http://memcachedb.org/
- http://tarantool.org/
- http://cassandra.apache.org/
- http://hyperdex.org/