<s>
IBM	B-Device
Sequoia	I-Device
was	O
a	O
petascale	B-General_Concept
Blue	B-General_Concept
Gene/Q	I-General_Concept
supercomputer	B-Architecture
constructed	O
by	O
IBM	O
for	O
the	O
National	O
Nuclear	O
Security	O
Administration	O
as	O
part	O
of	O
the	O
Advanced	B-General_Concept
Simulation	I-General_Concept
and	I-General_Concept
Computing	I-General_Concept
Program	I-General_Concept
(	O
ASC	O
)	O
.	O
</s>
<s>
Sequoia	B-Device
was	O
dismantled	O
in	O
2020	O
,	O
its	O
last	O
position	O
on	O
the	O
top500.org	B-Operating_System
list	O
was	O
#22	O
in	O
the	O
November	O
2019	O
list	O
.	O
</s>
<s>
On	O
June	O
14	O
,	O
2012	O
,	O
the	O
TOP500	B-Operating_System
Project	O
Committee	O
announced	O
that	O
Sequoia	B-Device
replaced	O
the	O
K	B-Device
computer	I-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
17.17	O
petaflops	O
,	O
63%	O
faster	O
than	O
the	O
K	B-Device
computer	I-Device
's	O
10.51	O
petaflops	O
,	O
having	O
123%	O
more	O
cores	O
than	O
the	O
K	B-Device
computer	I-Device
's	O
705,024	O
cores	O
.	O
</s>
<s>
Sequoia	B-Device
is	O
also	O
more	O
energy	O
efficient	O
,	O
as	O
it	O
consumes	O
7.9MW	O
,	O
37%	O
less	O
than	O
the	O
K	B-Device
computer	I-Device
's	O
12.6MW	O
.	O
</s>
<s>
,	O
Sequoia	B-Device
had	O
dropped	O
to	O
sixth	O
place	O
on	O
the	O
TOP500	B-Operating_System
ranking	O
,	O
while	O
it	O
was	O
at	O
third	O
position	O
on	O
June	O
17	O
,	O
2013	O
,	O
behind	O
Tianhe-2	B-Device
and	O
Titan	B-Device
.	O
</s>
<s>
In	O
June	O
2016	O
,	O
it	O
slipped	O
again	O
,	O
to	O
fourth	O
place	O
on	O
the	O
TOP500	B-Operating_System
ranking	O
.	O
</s>
<s>
In	O
June	O
2017	O
,	O
it	O
slipped	O
again	O
,	O
to	O
fifth	O
place	O
on	O
the	O
TOP500	B-Operating_System
ranking	O
.	O
</s>
<s>
Record-breaking	O
science	O
applications	O
have	O
been	O
run	O
on	O
Sequoia	B-Device
,	O
the	O
first	O
to	O
cross	O
10	O
petaflops	O
of	O
sustained	O
performance	O
.	O
</s>
<s>
The	O
entire	O
supercomputer	B-Architecture
runs	O
on	O
Linux	O
,	O
with	O
CNK	B-Operating_System
running	O
on	O
over	O
98,000	O
nodes	O
,	O
and	O
Red	O
Hat	O
Enterprise	O
Linux	O
running	O
on	O
768	O
I/O	O
nodes	O
that	O
are	O
connected	O
to	O
the	O
Lustre	B-Application
filesystem	O
.	O
</s>
<s>
IBM	O
built	O
a	O
prototype	O
,	O
called	O
"	O
Dawn	O
"	O
,	O
capable	O
of	O
500	O
teraflops	O
,	O
using	O
the	O
Blue	B-Operating_System
Gene/P	I-Operating_System
design	O
,	O
to	O
evaluate	O
the	O
Sequoia	B-Device
design	O
.	O
</s>
<s>
This	O
system	O
was	O
delivered	O
in	O
April	O
2009	O
and	O
entered	O
the	O
Top500	B-Operating_System
list	O
at	O
9th	O
place	O
in	O
June	O
2009	O
.	O
</s>
<s>
Sequoia	B-Device
was	O
used	O
primarily	O
for	O
nuclear	O
weapons	O
simulation	O
,	O
replacing	O
the	O
current	O
Blue	B-Operating_System
Gene/L	I-Operating_System
and	O
ASC	B-Device
Purple	I-Device
supercomputers	I-Device
at	O
Lawrence	O
Livermore	O
National	O
Laboratory	O
.	O
</s>
<s>
Sequoia	B-Device
was	O
also	O
available	O
for	O
scientific	O
purposes	O
such	O
as	O
astronomy	O
,	O
energy	O
,	O
lattice	O
QCD	O
,	O
study	O
of	O
the	O
human	O
genome	O
,	O
and	O
climate	O
change	O
.	O
</s>
<s>
Sequoia	B-Device
was	O
a	O
Blue	B-General_Concept
Gene/Q	I-General_Concept
design	O
,	O
based	O
on	O
previous	O
Blue	B-Operating_System
Gene	I-Operating_System
designs	O
.	O
</s>
<s>
It	O
consisted	O
of	O
96	O
racks	B-Application
containing	O
98,304	O
compute	O
nodes	O
,	O
i.e.	O
,	O
1024	O
per	O
rack	O
.	O
</s>
<s>
The	O
compute	O
nodes	O
were	O
16-core	O
A2	B-Device
processor	O
chips	O
with	O
16GB	O
of	O
DDR3	O
memory	O
each	O
.	O
</s>
<s>
Thus	O
,	O
the	O
system	O
contained	O
a	O
total	O
of	O
96·1024·16	O
=	O
1,572,864	O
processor	B-Architecture
cores	I-Architecture
with	O
1.5PiB	O
memory	O
.	O
</s>
<s>
The	O
compute	O
nodes	O
were	O
interconnected	O
in	O
a	O
5-dimensional	O
torus	B-Operating_System
topology	O
.	O
</s>
<s>
LLNL	O
used	O
the	O
SLURM	B-Operating_System
job	O
scheduler	O
,	O
also	O
used	O
by	O
the	O
Dawn	O
prototype	O
and	O
China	O
's	O
Tianhe-IA	O
,	O
to	O
manage	O
Sequoia	B-Device
's	O
resources	O
.	O
</s>
<s>
LLNL	O
uses	O
Lustre	B-Application
as	O
the	O
parallel	O
filesystem	O
,	O
and	O
has	O
ported	O
ZFS	B-Application
to	O
Linux	O
as	O
the	O
Lustre	B-Application
OSD	O
(	O
Object	O
Storage	O
Device	O
)	O
to	O
take	O
advantage	O
of	O
the	O
performance	O
and	O
advanced	O
features	O
of	O
the	O
filesystem	O
.	O
</s>
<s>
The	O
complete	O
system	O
drew	O
about	O
7.8MW	O
of	O
power	O
,	O
but	O
had	O
a	O
unprecedented	O
energy	O
efficiency	O
,	O
performing	O
2068Mflops/watt	O
,	O
about	O
6	O
times	O
as	O
efficient	O
as	O
Dawn	O
,	O
and	O
more	O
than	O
2.5	O
times	O
as	O
efficient	O
as	O
the	B-Device
June	I-Device
2011	I-Device
Top	I-Device
500	I-Device
leader	I-Device
.	O
</s>
<s>
In	O
January	O
2013	O
,	O
Sequoia	B-Device
set	O
the	O
record	O
for	O
the	O
first	O
supercomputer	B-Architecture
using	O
more	O
than	O
one	O
million	O
computing	O
cores	O
at	O
a	O
time	O
for	O
a	O
single	O
application	O
.	O
</s>
