<s>
HPFS	O
(	O
High	O
Performance	O
File	B-Application
System	I-Application
)	O
is	O
a	O
file	B-Application
system	I-Application
created	O
specifically	O
for	O
the	O
OS/2	B-Application
operating	B-General_Concept
system	I-General_Concept
to	O
improve	O
upon	O
the	O
limitations	O
of	O
the	O
FAT	B-Application
file	I-Application
system	I-Application
.	O
</s>
<s>
It	O
was	O
written	O
by	O
Gordon	O
Letwin	O
and	O
others	O
at	O
Microsoft	O
and	O
added	O
to	O
OS/2	B-Application
version	O
1.2	O
,	O
at	O
that	O
time	O
still	O
a	O
joint	O
undertaking	O
of	O
Microsoft	O
and	O
IBM	O
,	O
and	O
released	O
in	O
1988	O
.	O
</s>
<s>
Compared	O
with	O
FAT	B-Application
,	O
HPFS	O
provided	O
a	O
number	O
of	O
additional	O
capabilities	O
:	O
</s>
<s>
HPFS	O
also	O
can	O
keep	O
64	O
KB	O
of	O
metadata	O
(	O
"	O
extended	B-Application
attributes	I-Application
"	O
)	O
per	O
file	O
.	O
</s>
<s>
IBM	O
offers	O
two	O
kinds	O
of	O
IFS	B-Application
drivers	O
for	O
this	O
file	B-Application
system	I-Application
:	O
</s>
<s>
HPFS386	O
's	O
cache	O
is	O
limited	O
by	O
the	O
amount	O
of	O
available	O
memory	O
in	O
OS/2	B-Application
'	O
s	O
system	O
memory	O
arena	O
and	O
was	O
implemented	O
in	O
32-bit	O
assembly	B-Language
language	I-Language
.	O
</s>
<s>
HPFS386	O
is	O
a	O
ring	B-Operating_System
0	I-Operating_System
driver	O
(	O
allowing	O
direct	O
hardware	O
access	O
and	O
direct	O
interaction	O
with	O
the	O
kernel	O
)	O
with	O
built-in	O
SMB	O
networking	O
properties	O
that	O
are	O
usable	O
by	O
various	O
server	O
daemons	B-Operating_System
,	O
whereas	O
HPFS	O
is	O
a	O
ring	B-Operating_System
3	I-Operating_System
driver	O
.	O
</s>
<s>
This	O
was	O
a	O
result	O
of	O
the	O
Microsoft	O
and	O
IBM	O
collaboration	O
that	O
gave	O
both	O
the	O
right	O
to	O
use	O
Windows	O
and	O
OS/2	B-Application
technology	O
.	O
</s>
<s>
Due	O
to	O
the	O
Microsoft	O
dependence	O
,	O
limited	O
partition	O
size	O
,	O
file	O
size	O
limit	O
of	O
2GB	O
and	O
the	O
long	O
disk-check	O
times	O
after	O
a	O
crash	O
,	O
IBM	O
ported	O
the	O
journaling	B-Application
file	I-Application
system	I-Application
JFS	B-Application
to	O
OS/2	B-Application
as	O
a	O
substitute	O
.	O
</s>
<s>
DOS	B-Device
and	O
Linux	B-Application
support	O
HPFS	O
via	O
third-party	O
drivers	O
.	O
</s>
<s>
Windows	B-Device
NT	I-Device
versions	O
3.51	O
and	O
earlier	O
had	O
native	O
support	O
for	O
HPFS	O
.	O
</s>
<s>
Windows	B-Application
95	I-Application
and	O
its	O
successors	O
Windows	B-Device
98	I-Device
and	O
Windows	B-Device
Me	I-Device
can	O
read	O
and	O
write	O
HPFS	O
only	O
when	O
mapped	O
via	O
a	O
network	O
share	O
;	O
they	O
cannot	O
read	O
it	O
from	O
a	O
local	O
disk	O
.	O
</s>
<s>
They	O
listed	O
the	O
NTFS	B-Application
partitions	O
of	O
networked	O
computers	O
as	O
"	O
HPFS	O
"	O
,	O
because	O
NTFS	B-Application
and	O
HPFS	O
share	O
the	O
same	O
filesystem	B-Application
identification	I-Application
number	I-Application
in	O
the	O
partition	O
table	O
.	O
</s>
<s>
Windows	B-Device
NT	I-Device
3.1	I-Device
and	O
3.5	B-Device
have	O
native	O
read/write	O
support	O
for	O
local	O
disks	O
and	O
can	O
even	O
be	O
installed	O
onto	O
an	O
HPFS	O
partition	O
.	O
</s>
<s>
Windows	B-Device
NT	I-Device
3.51	I-Device
can	O
also	O
read	O
and	O
write	O
from	O
local	O
HPFS	O
formatted	O
drives	O
.	O
</s>
<s>
Starting	O
with	O
Windows	B-Device
NT	I-Device
4	I-Device
the	O
filesystem	B-Application
driver	O
PINBALL.SYS	B-Device
enabling	O
the	O
read/write	O
access	O
is	O
not	O
shipped	O
anymore	O
.	O
</s>
<s>
Microsoft	O
retained	O
rights	O
to	O
OS/2	B-Application
technologies	O
,	O
including	O
the	O
HPFS	O
filesystem	B-Application
,	O
after	O
they	O
ceased	O
collaboration	O
with	O
IBM	O
.	O
</s>
<s>
Since	O
Windows	B-Device
NT	I-Device
3.1	I-Device
was	O
designed	O
for	O
more	O
rigorous	O
(	O
enterprise-class	O
)	O
use	O
than	O
previous	O
versions	O
of	O
Windows	O
,	O
it	O
included	O
support	O
for	O
HPFS	O
(	O
and	O
NTFS	B-Application
)	O
giving	O
it	O
a	O
larger	O
storage	O
capacity	O
than	O
the	O
FAT12	B-Application
and	O
FAT16	B-Application
filesystems	B-Application
.	O
</s>
<s>
However	O
,	O
since	O
HPFS	O
lacks	O
a	O
journal	B-Application
,	O
any	O
recovery	O
after	O
an	O
unexpected	O
shutdown	O
or	O
other	O
error	O
state	O
takes	O
progressively	O
longer	O
as	O
the	O
filesystem	B-Application
grows	O
.	O
</s>
<s>
A	O
utility	O
such	O
as	O
CHKDSK	B-Device
would	O
need	O
to	O
scan	O
each	O
entry	O
in	O
the	O
filesystem	B-Application
to	O
ensure	O
no	O
errors	O
are	O
present	O
,	O
a	O
problem	O
which	O
is	O
vastly	O
reduced	O
on	O
NTFS	B-Application
,	O
which	O
simply	O
replays	O
the	O
journal	B-Application
.	O
</s>
