<s>
Structured	B-General_Concept
storage	I-General_Concept
is	O
computer	B-General_Concept
storage	I-General_Concept
for	O
structured	B-General_Concept
data	I-General_Concept
,	O
often	O
in	O
the	O
form	O
of	O
a	O
distributed	B-Operating_System
database	I-Operating_System
.	O
</s>
<s>
Computer	B-Application
software	I-Application
formally	O
known	O
as	O
structured	B-General_Concept
storage	I-General_Concept
systems	O
include	O
Apache	B-Application
Cassandra	I-Application
,	O
Google	B-Application
's	I-Application
Bigtable	B-Application
and	O
Apache	B-Language
HBase	I-Language
.	O
</s>
<s>
The	O
following	O
is	O
a	O
comparison	O
of	O
notable	O
structured	B-General_Concept
storage	I-General_Concept
systems	O
.	O
</s>
<s>
Project	O
Name	O
Type	O
Persistence	B-Application
Replication	B-Architecture
High	O
Availability	O
Transactions	B-General_Concept
Rack-locality	O
Awareness	O
Implementation	O
Language	O
Influences	O
,	O
Sponsors	O
License	B-License
Aerospike	B-Operating_System
NoSQL	B-General_Concept
database	O
,	O
Hybrid	O
DRAM	O
and	O
flash	O
for	O
persistence	B-Application
,	O
Distributed	O
for	O
scale	O
C	B-Language
(	O
small	O
bits	O
of	O
assembly	B-Language
language	I-Language
)	O
Aerospike	B-Operating_System
AGPL	O
v3	O
AllegroGraph	B-Language
Graph	B-Application
database	I-Application
No	O
-	O
v5	O
,	O
2010	O
Common	B-Language
Lisp	I-Language
Franz	O
Inc	O
.	O
</s>
<s>
Proprietary	B-Application
Apache	B-Application
Ignite	I-Application
Key-value	O
To	O
and	O
from	O
an	O
underlying	O
persistent	B-Application
storage	I-Application
(	O
e.g.	O
</s>
<s>
an	O
RDBMS	B-Application
)	O
Java	B-Language
Apache	O
,	O
GridGain	O
Systems	O
Apache	B-Application
2.0	I-Application
Apache	B-Language
Jackrabbit	I-Language
Key-value	O
&	O
Hierarchical	O
&	O
Document	O
likely	O
Java	B-Language
Apache	O
,	O
Roy	O
Fielding	O
,	O
Day	O
Software	O
Apache	B-Application
2.0	I-Application
Berkeley	O
DB/Dbm	O
1.x	O
Key-value	O
C	B-Language
old	O
school	O
Various	O
Berkeley	B-Language
DB	I-Language
Sleepycat/Oracle	O
Berkeley	B-Language
DB	I-Language
5.x	O
Key-value	O
C	B-Language
,	O
C++	B-Language
,	O
or	O
Java	B-Language
dbm	B-General_Concept
,	O
Sleepycat/Oracle	O
dual	O
GPL-like	O
Sleepycat	O
License	B-License
Apache	B-Application
Cassandra	I-Application
Key-value	O
Distributed	O
Only	O
supports	O
CAS	O
(	O
Check	O
And	O
Set	O
)	O
after	O
2.1.1	O
and	O
laterjava	O
-	O
Cassandra	B-Application
-	O
transaction	O
support	O
-	O
Stack	O
OverflowLightweight	O
transactions	B-General_Concept
Java	B-Language
Dynamo	O
and	O
Bigtable	B-Application
,	O
Facebook/Digg/Rackspace	O
Apache	B-Application
2.0	I-Application
ClustrixDB	O
scale-out	O
relational	O
Distributed	O
and	O
Replication	B-Architecture
C	B-Language
Clustrix	O
Proprietary	B-Application
Coherence	B-Application
Key-value	O
Persistent	O
data	O
typically	O
in	O
an	O
RDBMS	B-Application
Java	B-Language
Oracle	B-Application
(	O
previously	O
Tangosol	O
)	O
Proprietary	B-Application
Oracle	B-Application
NoSQL	I-Application
Database	I-Application
Key-value	O
Java	B-Language
Oracle	B-Application
AGPLv3	O
License	B-License
or	O
proprietary	B-Application
Couchbase	B-Operating_System
Document	O
,	O
with	O
two-phase	O
commitsProviding	O
transactional	O
logic	O
C++	B-Language
,	O
Erlang	B-Operating_System
,	O
C	B-Language
,	O
Go	B-Application
CouchDB	B-Application
,	O
Memcached	B-Application
Apache	B-Application
2.0	I-Application
CouchDB	B-Application
Document	O
replication	B-Architecture
+	O
load	O
balancing	O
Atomicity	O
is	O
per	O
document	O
,	O
per	O
CouchDB	B-Application
instance	O
Erlang	B-Operating_System
Lotus	O
Notes	O
/	O
Ubuntu	O
,	O
Mozilla	O
,	O
IBM	O
Apache	B-Application
2.0	I-Application
Extensible	O
Storage	O
Engine( 	O
ESE/NT	O
)	O
Document	O
or	O
Key-value	O
C++	B-Language
,	O
Assembly	O
Microsoft	O
Proprietary	B-Application
FoundationDB	B-Operating_System
Ordered	O
Key-value	O
Depends	O
on	O
user	O
configuration	O
C++	B-Language
FoundationDB	B-Operating_System
Proprietary	B-Application
GT.M	B-Application
Key-value	O
Depends	O
on	O
user	O
configuration	O
C	B-Language
(	O
small	O
bits	O
of	O
assembly	B-Language
language	I-Language
)	O
FIS	O
AGPL	O
v3	O
Project	O
Name	O
Type	O
Persistence	B-Application
Replication	B-Architecture
High	O
Availability	O
Transactions	B-General_Concept
Rack-locality	O
Awareness	O
Implementation	O
Language	O
Influences	O
,	O
Sponsors	O
License	B-License
Apache	B-Language
HBase	I-Language
Key-value	O
.	O
</s>
<s>
HDFS	O
,	O
HBase	B-Language
:	O
Bigtable-like	O
structured	B-General_Concept
storage	I-General_Concept
for	O
Hadoop	O
HDFS	O
Amazon	O
S3HBase	O
on	O
EC2	O
or	O
Amazon	O
Elastic	O
Block	O
Store.HBase	O
on	O
EC2	O
using	O
EBS	O
volumes	O
:	O
Lessons	O
Learned	O
|	O
My	O
AWS	O
Musings	O
Hbase/MultipleMasters	O
-	O
Hadoop	O
Wiki	O
ACID	O
in	O
HBase	B-Language
See	O
HDFS	O
,	O
S3	O
or	O
EBS	O
.	O
</s>
<s>
Java	B-Language
Bigtable	B-Application
Apache	B-Application
2.0	I-Application
Hypertable	B-General_Concept
Key-value	O
,	O
with	O
KosmosFS	O
and	O
Ceph	O
coming	O
in	O
2.0	O
coming	O
,	O
with	O
KosmosFS	O
C++	B-Language
Bigtable	B-Application
GPL	B-License
2.0	I-License
Information	B-Application
Management	I-Application
System	I-Application
IBM	B-Application
IMS	I-Application
aka	O
DB1	O
Key-value	O
.	O
</s>
<s>
Multi-level	O
,	O
with	O
HALDB	O
,	O
with	O
IMS	O
TM	O
Unknown	O
Assembler	B-Language
IBM	O
since	O
1966	O
Proprietary	B-Application
Infinispan	B-Language
Key-value	O
Java	B-Language
Red	O
Hat	O
Apache	B-Application
2.0	I-Application
Memcached	B-Application
Key-value	O
Only	O
supports	O
CAS	O
(	O
Check	O
And	O
Set	O
-	O
or	O
Compare	O
And	O
Swap	O
)	O
sql	O
-	O
Memcache	B-Application
with	O
transactions	B-General_Concept
?	O
</s>
<s>
-	O
Stack	O
OverflowMemcached	O
C	B-Language
Six	O
Apart/Couchbase/Fotolog/Facebook	O
BSD-like	O
permissive	O
copyright	O
by	O
Danga	O
LevelDB	B-Language
Key-value	O
,	O
Bigtable	B-Application
Multiple	O
writes	O
can	O
be	O
combined	O
into	O
single	O
operation	O
C++	B-Language
Google	B-Application
New	O
BSD	B-Operating_System
License	I-Operating_System
LightningDB	B-Language
Key-value	O
,	O
memory-mapped	O
files	O
,	O
ACID	O
,	O
MVCC	O
C	B-Language
Symas	O
OpenLDAP	O
Public	O
License	B-License
MongoDB	B-Application
Document	O
(	O
JSON	O
)	O
fail-over	O
Single	O
document	O
atomicityAtomic	O
Operations	O
-	O
MongoDB	B-Application
C++	B-Language
10gen	O
GNU	O
AGPL	O
v3.0	O
Neo4j	B-Language
Graph	B-Application
database	I-Application
Java	B-Language
Neo	B-Language
Technology	I-Language
GNU	B-License
GPL	I-License
v3.0	I-License
OrientDB	B-Operating_System
Multi-Model	O
(	O
Graph-Document-Object-Key/Value	O
)	O
Java	B-Language
Orient	O
Technologies	O
Apache	B-Application
2.0	I-Application
Redis	B-Operating_System
Key-value	O
.	O
</s>
<s>
But	O
last	O
few	O
queries	O
can	O
be	O
lost.Redis	O
Persistence	B-Application
high	O
availability	O
-	O
Redis	B-Operating_System
master/slave	O
replication	B-Architecture
-	O
single	O
point	O
of	O
failure	O
?	O
</s>
<s>
-	O
Stack	O
Overflow	O
Transactions	B-General_Concept
–	O
Redis	B-Operating_System
Ansi-C	O
VMWare	O
,	O
Memcache	B-Application
BSD	B-Operating_System
Scylla	B-Language
Key-value	O
Distributed	O
and	O
Replication	B-Architecture
Unknown	O
C++	B-Language
Apache	B-Application
Cassandra	I-Application
AGPL	O
v3	O
SimpleDB	O
(	O
Amazon.com	O
)	O
Document	O
&	O
Key-value	O
(	O
automatic	O
)	O
Unknown	O
likely	O
Erlang	B-Operating_System
Amazon.com	O
Amazon	O
internal	O
only	O
Tarantool	B-Operating_System
Free-dimensional	O
tuples	O
with	O
primary	O
and	O
secondary	O
keys	O
.	O
</s>
