<s>
AdvFS	B-Application
,	O
also	O
known	O
as	O
Tru64	B-Operating_System
UNIX	I-Operating_System
Advanced	O
File	B-Application
System	I-Application
,	O
is	O
a	O
file	B-Application
system	I-Application
developed	O
in	O
the	O
late	O
1980s	O
to	O
mid-1990s	O
by	O
Digital	O
Equipment	O
Corporation	O
for	O
their	O
OSF/1	B-Operating_System
version	O
of	O
the	O
Unix	B-Application
operating	I-Application
system	I-Application
(	O
later	O
Digital	O
UNIX/Tru64	O
UNIX	O
)	O
.	O
</s>
<s>
In	O
June	O
2008	O
,	O
it	O
was	O
released	O
as	O
free	O
software	O
under	O
the	O
GPL-2.0-only	B-License
license	O
.	O
</s>
<s>
AdvFS	B-Application
has	O
been	O
used	O
in	O
high-availability	O
systems	O
where	O
fast	O
recovery	O
from	O
downtime	O
is	O
essential	O
.	O
</s>
<s>
AdvFS	B-Application
uses	O
a	O
relatively	O
advanced	O
concept	O
of	O
a	O
storage	O
pool	O
(	O
called	O
a	O
file	O
domain	O
)	O
and	O
of	O
logical	O
file	B-Application
systems	I-Application
(	O
called	O
file	O
sets	O
)	O
.	O
</s>
<s>
A	O
file	O
domain	O
is	O
composed	O
of	O
any	O
number	O
of	O
block	O
devices	O
,	O
which	O
could	O
be	O
partitions	O
,	O
LVM	B-Application
or	O
LSM	O
devices	O
.	O
</s>
<s>
A	O
file	O
set	O
is	O
a	O
logical	O
file	B-Application
system	I-Application
created	O
in	O
a	O
single	O
file	O
domain	O
.	O
</s>
<s>
Under	O
Linux	B-Operating_System
,	O
AdvFS	B-Application
supports	O
an	O
additional	O
‘’	O
syncv’’	O
system	O
call	O
to	O
atomically	O
commit	O
changes	O
to	O
multiple	O
files	O
.	O
</s>
<s>
AdvFS	B-Application
,	O
also	O
known	O
as	O
Tru64	B-Operating_System
UNIX	I-Operating_System
Advanced	O
File	B-Application
System	I-Application
,	O
was	O
developed	O
by	O
Digital	O
Equipment	O
Corporation	O
engineers	O
in	O
the	O
late	O
1980s	O
to	O
mid-1990s	O
in	O
Bellevue	O
,	O
WA	O
(	O
DECwest	O
)	O
.	O
</s>
<s>
They	O
had	O
previously	O
worked	O
on	O
the	O
earlier	O
(	O
cancelled	O
)	O
MICA	B-Operating_System
and	I-Operating_System
OZIX	I-Operating_System
projects	O
there	O
.	O
</s>
<s>
It	O
was	O
first	O
delivered	O
on	O
the	O
DEC	B-Operating_System
OSF/1	I-Operating_System
system	O
(	O
later	O
Digital	O
UNIX/Tru64	O
UNIX	O
)	O
.	O
</s>
<s>
Thus	O
,	O
DEC	B-Operating_System
OSF/1	I-Operating_System
v3.2	O
had	O
AdvFS	B-Application
v2.x	O
,	O
Digital	B-Operating_System
UNIX	I-Operating_System
4.0	O
had	O
AdvFS	B-Application
v3.x	O
and	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.x	O
had	O
AdvFS	B-Application
v4.x	O
.	O
</s>
<s>
It	O
is	O
generally	O
considered	O
that	O
only	O
AdvFS	B-Application
v4	O
had	O
matured	O
to	O
production	O
level	O
stability	O
,	O
with	O
a	O
sufficient	O
set	O
of	O
tools	O
to	O
get	O
administrators	O
out	O
of	O
any	O
kind	O
of	O
trouble	O
.	O
</s>
<s>
The	O
original	O
team	O
had	O
enough	O
confidence	O
in	O
its	O
log	O
based	O
recovery	O
to	O
release	O
it	O
without	O
an	O
"	O
fsck	O
"	O
style	O
recovery	O
utility	O
on	O
the	O
assumption	O
that	O
the	O
file	B-Application
system	I-Application
journal	B-Application
would	O
always	O
be	O
allocated	O
on	O
mirrored	O
drives	O
.	O
</s>
<s>
In	O
1996	O
,	O
Lee	O
and	O
Thekkath	O
described	O
the	O
use	O
of	O
AdvFS	B-Application
on	O
top	O
of	O
a	O
novel	O
disk	O
virtualisation	O
layer	O
known	O
as	O
Petal	O
.	O
</s>
<s>
describe	O
their	O
own	O
file	B-Application
system	I-Application
(	O
Frangipani	O
)	O
built	O
on	O
top	O
of	O
Petal	O
and	O
compare	O
it	O
to	O
the	O
performance	O
of	O
AdvFS	B-Application
running	O
on	O
the	O
same	O
storage	O
layer	O
.	O
</s>
<s>
Shapiro	O
and	O
Miller	O
compared	O
the	O
performance	O
of	O
files	O
stored	O
in	O
AdvFS	B-Application
to	O
Oracle	O
RDBMS	O
version	O
7.3.4	O
BLOB	O
storage	O
.	O
</s>
<s>
Compaq	O
Sierra	O
Parallel	O
File	B-Application
System	I-Application
(	O
PFS	O
)	O
created	O
a	O
cluster	O
file	B-Application
system	I-Application
based	O
on	O
multiple	O
local	O
AdvFS	B-Application
filesystems	B-Application
;	O
testing	O
carried	O
out	O
at	O
Lawrence	O
Livermore	O
National	O
Laboratory	O
(	O
LLNL	O
)	O
in	O
2000	O
–	O
2001	O
found	O
that	O
while	O
the	O
underlying	O
AdvFS	B-Application
filesystem	B-Application
had	O
adequate	O
performance	O
(	O
albeit	O
with	O
high	O
CPU	O
utilisation	O
)	O
,	O
the	O
PFS	O
clustering	O
layer	O
on	O
top	O
of	O
it	O
performed	O
poorly	O
.	O
</s>
<s>
On	O
June	O
23	O
,	O
2008	O
,	O
its	O
source	O
code	O
was	O
released	O
by	O
Hewlett-Packard	O
under	O
the	O
GPL-2.0-only	B-License
license	O
(	O
instead	O
of	O
the	O
recently	O
released	O
GPLv3	O
)	O
at	O
SourceForge	B-Application
in	O
order	O
to	O
be	O
compatible	O
with	O
the	O
also	O
GPL-2.0-only	B-License
licensed	O
Linux	B-Operating_System
kernel	I-Operating_System
.	O
</s>
