<s>
The	O
Oracle	B-Application
Cluster	I-Application
File	I-Application
System	I-Application
(	O
OCFS	B-Application
,	O
in	O
its	O
second	O
version	O
OCFS2	B-Application
)	O
is	O
a	O
shared	O
disk	O
file	O
system	O
developed	O
by	O
Oracle	B-Application
Corporation	I-Application
and	O
released	O
under	O
the	O
GNU	B-License
General	I-License
Public	I-License
License	I-License
.	O
</s>
<s>
The	O
first	O
version	O
of	O
OCFS	B-Application
was	O
developed	O
with	O
the	O
main	O
focus	O
to	O
accommodate	O
Oracle	B-Application
's	O
database	B-Application
management	I-Application
system	I-Application
that	O
used	O
cluster	B-Architecture
computing	I-Architecture
.	O
</s>
<s>
OCFS2	B-Application
(	O
version	O
2	O
)	O
was	O
integrated	O
into	O
the	O
version	O
2.6.16	O
of	O
Linux	B-Operating_System
kernel	I-Operating_System
.	O
</s>
<s>
This	O
restriction	O
was	O
removed	O
in	O
Linux	B-Operating_System
version	O
2.6.19	O
.	O
</s>
<s>
With	O
kernel	B-Operating_System
version	O
2.6.29	O
in	O
late	O
2008	O
,	O
more	O
features	O
were	O
included	O
into	O
ocfs2	B-Application
,	O
such	O
as	O
access	O
control	O
lists	O
and	O
quotas	O
.	O
</s>
<s>
OCFS2	B-Application
used	O
a	O
distributed	B-Operating_System
lock	I-Operating_System
manager	I-Operating_System
which	O
resembles	O
the	O
OpenVMS	B-Operating_System
DLM	O
but	O
is	O
much	O
simpler	O
.	O
</s>
<s>
Oracle	B-Application
announced	O
version	O
1.6	O
in	O
November	O
2010	O
which	O
included	O
a	O
copy	B-Language
on	I-Language
write	I-Language
feature	O
called	O
reflink	O
.	O
</s>
