List of scalable Key/Value Stores

For an overview of Consistency Models see Jepsen or Wikipedia.

Name	Consistency Model	Transactions	C Client	Notes
ctdb	Volatile DBs: Sequential Consistency Persistent DBs: Linearizability	No Yes	yes
etcd	Linearizability	Yes ("mini")	yes	Performance?
Ceph Rados	Linearizability	?	yes
Apache Cassandra	Strong Partition Serializability New: Strict Serializability [1]	yes	yes
Apache HBase	?	?	?
Apache Ignite	?	?	?
FoundationDB	Strict Serializability	yes	yes
CockroachDB	Serializable+, Strong Partition Serializability	?	yes
ScyllaDB	Single-key Linearizability with LWT	?	yes
YugabyteDB	Snapshot	?	yes
tikv	Strong Consistency [2]	yes	no (C++)
Apache Pegasus	?	?	no (C++)

List of Opensource Clustered Filesystems

Name	Built on-top of Object Storage	Notes
Ceph	yes
GlusterFS	no
JuiceFS	yes
MooseFS	no
ObjectiveFS	yes
Lustre	no