<s>
The	O
K	B-Device
computer	I-Device
named	O
for	O
the	O
Japanese	O
word/numeral	O
,	O
meaning	O
10	O
quadrillion	O
(	O
1016	O
)	O
was	O
a	O
supercomputer	B-Architecture
manufactured	O
by	O
Fujitsu	O
,	O
installed	O
at	O
the	O
Riken	O
Advanced	O
Institute	O
for	O
Computational	O
Science	O
campus	O
in	O
Kobe	O
,	O
Hyōgo	O
Prefecture	O
,	O
Japan	O
.	O
</s>
<s>
The	O
K	B-Device
computer	I-Device
was	O
based	O
on	O
a	O
distributed	B-Operating_System
memory	I-Operating_System
architecture	O
with	O
over	O
80,000	O
compute	O
nodes	O
.	O
</s>
<s>
The	O
K	B-Device
computer	I-Device
's	O
operating	B-General_Concept
system	I-General_Concept
was	O
based	O
on	O
the	O
Linux	B-Operating_System
kernel	I-Operating_System
,	O
with	O
additional	O
drivers	O
designed	O
to	O
make	O
use	O
of	O
the	O
computer	O
's	O
hardware	O
.	O
</s>
<s>
In	O
June	O
2011	O
,	O
TOP500	B-Operating_System
ranked	O
K	B-Device
the	O
world	O
's	O
fastest	B-Operating_System
supercomputer	I-Operating_System
,	O
with	O
a	O
computation	O
speed	O
of	O
over	O
8	O
petaflops	O
,	O
and	O
in	O
November	O
2011	O
,	O
K	B-Device
became	O
the	O
first	O
computer	O
to	O
top	O
10	O
petaflops	O
.	O
</s>
<s>
In	O
June	O
2012	O
,	O
K	B-Device
was	O
superseded	O
as	O
the	O
world	O
's	O
fastest	B-Operating_System
supercomputer	I-Operating_System
by	O
the	O
American	O
IBM	B-Device
Sequoia	I-Device
.	O
</s>
<s>
,	O
the	O
K	B-Device
computer	I-Device
holds	O
the	O
third	O
place	O
for	O
the	O
HPCG	B-Operating_System
benchmark	I-Operating_System
.	O
</s>
<s>
It	O
held	O
the	O
first	O
place	O
until	O
June	O
2018	O
,	O
when	O
it	O
was	O
superseded	O
by	O
Summit	B-Device
and	O
Sierra	B-Device
.	O
</s>
<s>
,	O
K	B-Device
is	O
the	O
world	O
's	O
20th-fastest	O
computer	O
,	O
with	O
the	O
IBM	O
's	O
Summit	B-Device
and	O
Sierra	B-Device
being	O
the	O
fastest	B-Operating_System
supercomputers	I-Operating_System
.	O
</s>
<s>
The	O
K	B-Device
supercomputer	I-Device
was	O
decommissioned	O
on	O
30	O
August	O
2019	O
.	O
</s>
<s>
In	O
Japan	O
,	O
the	O
K	B-Device
computer	I-Device
was	O
succeeded	O
by	O
the	O
Fugaku	B-Device
supercomputer	B-Architecture
,	O
in	O
2020	O
,	O
which	O
took	O
the	O
top	O
spot	O
,	O
and	O
is	O
three	O
times	O
faster	O
than	O
2nd	O
most	O
powerful	O
supercomputer	B-Architecture
.	O
</s>
<s>
On	O
20	O
June	O
2011	O
,	O
the	O
TOP500	B-Operating_System
Project	O
Committee	O
announced	O
that	O
K	B-Device
had	O
set	O
a	O
LINPACK	B-Application
record	O
with	O
a	O
performance	O
of	O
8.162	O
petaflops	O
,	O
making	O
it	O
the	O
fastest	B-Operating_System
supercomputer	I-Operating_System
in	O
the	O
world	O
at	O
the	O
time	O
;	O
it	O
achieved	O
this	O
performance	O
with	O
a	O
computing	O
efficiency	O
ratio	O
of	O
93.0	O
%	O
.	O
</s>
<s>
The	O
previous	O
record	O
holder	O
was	O
the	O
Chinese	O
National	O
University	O
of	O
Defense	O
Technology	O
's	O
Tianhe-1A	B-Device
,	O
which	O
performed	O
at	O
2.507	O
petaflops	O
.	O
</s>
<s>
The	O
TOP500	B-Operating_System
list	O
is	O
revised	O
semiannually	O
,	O
and	O
the	O
rankings	O
change	O
frequently	O
,	O
indicating	O
the	O
speed	O
at	O
which	O
computing	O
power	O
is	O
increasing	O
.	O
</s>
<s>
In	O
November	O
2011	O
,	O
Riken	O
reported	O
that	O
K	B-Device
had	O
become	O
the	O
first	O
supercomputer	B-Architecture
to	O
exceed	O
10	O
petaflops	O
,	O
achieving	O
a	O
LINPACK	B-Application
performance	O
of	O
10.51	O
quadrillion	O
computations	O
per	O
second	O
with	O
a	O
computing	O
efficiency	O
ratio	O
of	O
93.2	O
%	O
.	O
</s>
<s>
K	B-Device
received	O
top	O
ranking	O
in	O
all	O
four	O
performance	O
benchmarks	O
at	O
the	O
2011	O
HPC	B-Application
Challenge	I-Application
Awards	I-Application
.	O
</s>
<s>
On	O
18	O
June	O
2012	O
,	O
the	O
TOP500	B-Operating_System
Project	O
Committee	O
announced	O
that	O
the	O
California-based	O
IBM	B-Device
Sequoia	I-Device
supercomputer	B-Architecture
replaced	O
K	B-Device
as	O
the	O
world	O
's	O
fastest	B-Operating_System
supercomputer	I-Operating_System
,	O
with	O
a	O
LINPACK	B-Application
performance	O
of	O
16.325	O
petaflops	O
.	O
</s>
<s>
Sequoia	B-Device
is	O
55%	O
faster	O
than	O
K	B-Device
,	O
using	O
123%	O
more	O
CPU	O
processors	O
,	O
but	O
is	O
also	O
150%	O
more	O
energy	O
efficient	O
.	O
</s>
<s>
On	O
the	O
TOP500	B-Operating_System
list	O
,	O
it	O
became	O
first	O
in	O
June	O
2011	O
,	O
falling	O
down	O
through	O
time	O
to	O
lower	O
positions	O
,	O
to	O
eighteenth	O
in	O
November	O
2018	O
.	O
</s>
<s>
K	B-Device
computer	I-Device
holds	O
third	O
place	O
in	O
the	O
HPCG	B-Operating_System
benchmark	I-Operating_System
test	O
proposed	O
by	O
Jack	O
Dongarra	O
,	O
with	O
0.6027HPCGPFLOPS	O
in	O
November	O
2018	O
.	O
</s>
<s>
The	O
K	B-Device
computer	I-Device
comprises	O
88,128	O
2.0GHz	O
eight-core	B-Architecture
SPARC64	B-General_Concept
VIIIfx	I-General_Concept
processors	O
contained	O
in	O
864	O
cabinets	O
,	O
for	O
a	O
total	O
of	O
705,024	O
cores	O
,	O
manufactured	O
by	O
Fujitsu	O
with	O
45	O
nm	O
CMOS	B-Device
technology	O
.	O
</s>
<s>
Each	O
computing	O
node	O
contains	O
a	O
single	O
processor	B-General_Concept
and	O
16GB	O
of	O
memory	O
.	O
</s>
<s>
The	O
system	O
adopts	O
a	O
two-level	O
local/global	O
file	B-Application
system	I-Application
with	O
parallel/distributed	O
functions	O
,	O
and	O
provides	O
users	O
with	O
an	O
automatic	O
staging	B-General_Concept
function	O
for	O
moving	O
files	O
between	O
global	O
and	O
local	O
file	B-Application
systems	I-Application
.	O
</s>
<s>
Fujitsu	O
developed	O
an	O
optimized	O
parallel	O
file	B-Application
system	I-Application
based	O
on	O
Lustre	B-Application
,	O
called	O
the	O
Fujitsu	O
Exabyte	O
File	B-Application
System	I-Application
(	O
FEFS	O
)	O
,	O
which	O
is	O
scalable	O
to	O
several	O
hundred	O
petabytes	O
.	O
</s>
<s>
Although	O
the	O
K	B-Device
computer	I-Device
reported	O
the	O
highest	O
total	O
power	O
consumption	O
of	O
any	O
2011	O
TOP500	B-Operating_System
supercomputer	B-Architecture
(	O
9.89MW	O
the	O
equivalent	O
of	O
almost	O
10,000	O
suburban	O
homes	O
)	O
,	O
it	O
is	O
relatively	O
efficient	O
,	O
achieving	O
824.6	O
GFlop/kW	O
.	O
</s>
<s>
However	O
,	O
K	B-Device
's	O
power	O
efficiency	O
still	O
falls	O
far	O
short	O
of	O
the	O
2097.2	O
GFlops/kWatt	O
supercomputer	B-Architecture
record	O
set	O
by	O
IBM	O
's	O
NNSA/SC	O
Blue	O
Gene/Q	O
Prototype	O
2	O
.	O
</s>
<s>
According	O
to	O
TOP500	B-Operating_System
compiler	O
Jack	O
Dongarra	O
,	O
professor	O
of	O
electrical	O
engineering	O
and	O
computer	O
science	O
at	O
the	O
University	O
of	O
Tennessee	O
,	O
the	O
K	B-Device
computer	I-Device
's	O
performance	O
equals	O
"	O
one	O
million	O
linked	O
desktop	O
computers	O
"	O
.	O
</s>
<s>
On	O
1	O
July	O
2011	O
,	O
Kobe	O
's	O
Port	O
Island	O
Line	O
rapid	O
transit	O
system	O
renamed	O
one	O
of	O
its	O
stations	O
from	O
"	O
Port	O
Island	O
Minami	O
"	O
to	O
"	O
K	B-Device
Computer	I-Device
Mae	O
"	O
(	O
meaning	O
"	O
In	O
front	O
of	O
K	B-Device
Computer	I-Device
"	O
)	O
denoting	O
its	O
vicinity	O
.	O
</s>
