<s>
The	O
ETA10	B-Operating_System
is	O
a	O
vector	B-Operating_System
supercomputer	B-Architecture
designed	O
,	O
manufactured	O
,	O
and	O
marketed	O
by	O
ETA	O
Systems	O
,	O
a	O
spin-off	O
division	O
of	O
Control	O
Data	O
Corporation	O
(	O
CDC	O
)	O
.	O
</s>
<s>
The	O
ETA10	B-Operating_System
was	O
an	O
evolution	O
of	O
the	O
CDC	B-Device
Cyber	I-Device
205	O
,	O
which	O
can	O
trace	O
its	O
origins	O
back	O
to	O
the	O
CDC	B-Device
STAR-100	I-Device
,	O
one	O
of	O
the	O
first	O
vector	B-Operating_System
supercomputers	B-Architecture
to	O
be	O
developed	O
.	O
</s>
<s>
CDC	O
announced	O
it	O
was	O
creating	O
ETA	O
Systems	O
,	O
and	O
a	O
successor	O
to	O
the	O
Cyber	B-Device
205	I-Device
,	O
on	O
18	O
April	O
1983	O
at	O
the	O
Frontiers	O
of	O
Supercomputing	B-Architecture
conference	O
,	O
held	O
at	O
the	O
Los	O
Alamos	O
National	O
Laboratory	O
.	O
</s>
<s>
It	O
was	O
then	O
referred	O
to	O
tentatively	O
as	O
the	O
Cyber	B-Operating_System
2XX	I-Operating_System
,	O
and	O
later	O
as	O
the	O
GF-10	B-Operating_System
,	O
before	O
it	O
was	O
named	O
the	O
ETA10	B-Operating_System
.	O
</s>
<s>
The	O
supercomputer	B-Architecture
was	O
formally	O
announced	O
in	O
April	O
1987	O
at	O
an	O
event	O
held	O
at	O
its	O
first	O
customer	O
installation	O
,	O
the	O
Florida	O
State	O
University	O
,	O
Tallahassee	O
's	O
Scientific	O
Computational	O
Research	O
Institute	O
.	O
</s>
<s>
On	O
17	O
April	O
1989	O
,	O
CDC	O
abruptly	O
closed	O
ETA	O
Systems	O
due	O
to	O
ongoing	O
financial	O
losses	O
,	O
and	O
discontinued	O
production	O
of	O
the	O
ETA10	B-Operating_System
.	O
</s>
<s>
CDC	O
had	O
a	O
strong	O
history	O
of	O
creating	O
powerful	O
supercomputers	B-Architecture
,	O
starting	O
with	O
the	O
CDC	B-Device
6600	I-Device
.	O
</s>
<s>
After	O
a	O
disagreement	O
with	O
CDC	O
management	O
regarding	O
the	O
development	O
of	O
the	O
CDC	B-Device
8600	I-Device
,	O
he	O
went	O
on	O
to	O
form	O
his	O
own	O
supercomputer	B-Architecture
company	O
,	O
Cray	O
Research	O
.	O
</s>
<s>
Meanwhile	O
,	O
work	O
continued	O
at	O
CDC	O
in	O
developing	O
a	O
high-end	O
supercomputer	B-Architecture
,	O
the	O
CDC	O
STAR-100led	O
by	O
another	O
famous	O
architect	O
,	O
Neil	O
Lincoln	O
.	O
</s>
<s>
Cray	O
Research	O
's	O
Cray-1	B-Device
vector	B-Operating_System
supercomputer	B-Architecture
was	O
successful	O
,	O
beating	O
CDC	O
's	O
STAR-100	O
.	O
</s>
<s>
The	O
Cyber	B-Device
205	I-Device
was	O
moderately	O
successful	O
against	O
the	O
Cray-1	B-Device
'	O
s	O
successor	O
,	O
the	O
Cray	B-Device
X-MP	I-Device
.	O
</s>
<s>
It	O
became	O
apparent	O
to	O
CDC	O
's	O
top	O
management	O
that	O
it	O
needed	O
to	O
decrease	O
the	O
development	O
time	O
for	O
the	O
next	O
generation	O
computerthus	O
a	O
new	O
approach	O
was	O
considered	O
for	O
the	O
follow-on	O
to	O
the	O
Cyber	B-Device
205	I-Device
.	O
</s>
<s>
After	O
spinning	O
off	O
from	O
CDC	O
in	O
September	O
1983	O
,	O
ETA	O
set	O
a	O
goal	O
of	O
producing	O
a	O
supercomputer	B-Architecture
with	O
a	O
cycle	O
time	O
less	O
than	O
10ns	O
.	O
</s>
<s>
Among	O
these	O
was	O
the	O
use	O
of	O
liquid	O
nitrogen	O
for	O
cooling	O
the	O
CMOS-based	O
CPUs	O
.	O
</s>
<s>
The	O
ETA10	B-Operating_System
successfully	O
met	O
the	O
company	O
's	O
initial	O
goals	O
(	O
10GFLOPS	O
)	O
,	O
with	O
some	O
models	O
achieving	O
a	O
cycle	O
time	O
of	O
about	O
7ns	O
(	O
143MHz	O
)	O
-	O
considered	O
rapid	O
by	O
mid-1980s	O
standards	O
.	O
</s>
<s>
The	O
CMOS	B-Device
circuits	O
produced	O
only	O
a	O
fraction	O
of	O
the	O
heat	O
of	O
previous	O
ICs	O
.	O
</s>
<s>
The	O
ETA10	B-Operating_System
series	O
could	O
run	O
either	O
ETA	O
's	O
EOS	B-Operating_System
operating	B-General_Concept
system	I-General_Concept
,	O
which	O
was	O
widely	O
criticized	O
for	O
various	O
problems	O
,	O
or	O
a	O
port	O
by	O
Lachman	O
Associates	O
,	O
a	O
software	O
personnel	O
firm	O
,	O
of	O
UNIX	B-Operating_System
System	I-Operating_System
V	I-Operating_System
(	O
Release	O
3	O
)	O
.	O
</s>
<s>
While	O
EOS	B-Operating_System
suffered	O
a	O
reputation	O
for	O
poor	O
quality	O
,	O
ETA	O
's	O
UNIX	B-Application
was	O
better	O
received	O
by	O
customers	O
.	O
</s>
<s>
EOS	B-Operating_System
was	O
preceded	O
by	O
and	O
was	O
binary	O
executable	O
compatible	O
with	O
the	O
CDC	O
VSOS	O
operating	B-General_Concept
system	I-General_Concept
for	O
Cyber	B-Device
205	I-Device
.	O
</s>
<s>
Like	O
VSOS	O
,	O
EOS	B-Operating_System
had	O
demand	O
paged	O
virtual	B-Architecture
memory	I-Architecture
(	O
the	O
VS	O
part	O
)	O
with	O
2	O
pages	O
sizes	O
for	O
improved	O
virtual	B-Architecture
memory	I-Architecture
performance	O
with	O
the	O
ETA	O
's	O
faster	O
hardware	O
pipelines	O
.	O
</s>
<s>
Though	O
it	O
had	O
roots	O
in	O
the	O
interactive	O
Livermore	B-Operating_System
Time	I-Operating_System
Sharing	I-Operating_System
System	I-Operating_System
(	O
LTSS	O
)	O
,	O
VSOS	O
was	O
focused	O
as	O
a	O
batch-oriented	B-General_Concept
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
VSOS	O
was	O
not	O
run	O
at	O
very	O
many	O
institutions	O
and	O
its	O
application-oriented	O
performance	O
,	O
while	O
the	O
historic	O
focus	O
for	O
supercomputing	B-Architecture
,	O
set	O
its	O
features	O
behind	O
the	O
times	O
because	O
of	O
its	O
limited	O
user	O
base	O
.	O
</s>
<s>
To	O
address	O
this	O
feature	O
deficiency	O
and	O
to	O
make	O
the	O
operating	B-General_Concept
system	I-General_Concept
more	O
"	O
normal	O
to	O
use	O
"	O
,	O
the	O
VSOS	O
characteristics	O
were	O
married	O
with	O
UNIX	B-Application
characteristics	O
in	O
a	O
hybrid	O
OS	O
.	O
</s>
<s>
The	O
OS	O
was	O
intended	O
to	O
be	O
effective	O
for	O
both	O
batch	O
work	O
that	O
drove	O
the	O
hardware	O
to	O
its	O
maximum	O
or	O
for	O
interactive	O
use	O
in	O
development	O
from	O
a	O
UNIX	B-Application
workstation	O
.	O
</s>
<s>
EOS	B-Operating_System
was	O
written	O
mainly	O
in	O
Cybil	B-Language
,	O
a	O
Pascal-like	O
programming	O
language	O
created	O
by	O
Control	O
Data	O
for	O
its	O
later	O
Cyber	O
operating	B-General_Concept
systems	I-General_Concept
.	O
</s>
<s>
It	O
was	O
a	O
new	O
effort	O
,	O
as	O
VSOS	O
was	O
implemented	O
in	O
IMPL	O
,	O
a	O
Fortran-like	O
language	O
created	O
for	O
the	O
LTSS	O
implementation	O
.	O
</s>
<s>
The	O
command	B-Application
line	I-Application
appearance	O
of	O
all	O
these	O
systems	O
was	O
similar	O
to	O
the	O
lineage	O
going	O
back	O
to	O
UNIVAC	O
EXEC*8	O
.	O
</s>
<s>
EOS	B-Operating_System
was	O
released	O
with	O
early	O
hardware	O
deliveries	O
and	O
had	O
some	O
of	O
the	O
typical	O
problems	O
for	O
early	O
OS	O
releases	O
.	O
</s>
<s>
Some	O
customers	O
delayed	O
payment	O
for	O
their	O
supercomputer	B-Architecture
installations	O
.	O
</s>
<s>
ETA	O
later	O
released	O
a	O
port	O
of	O
UNIX	B-Application
for	O
the	O
ETA-10	B-Operating_System
line	O
,	O
which	O
was	O
more	O
quickly	O
accepted	O
by	O
their	O
customer	O
base	O
.	O
</s>
<s>
Despite	O
eventual	O
adoption	O
of	O
UNIX	B-Application
,	O
poorly	O
developed	O
system	O
software	O
remained	O
one	O
flaw	O
of	O
the	O
ETA10	B-Operating_System
line	O
.	O
</s>
<s>
The	O
NSF	O
review	O
panel	O
found	O
that	O
the	O
ETA10	B-Operating_System
suffered	O
a	O
software	O
failure	O
once	O
every	O
30	O
hours	O
,	O
and	O
that	O
its	O
ability	O
to	O
run	O
programs	O
on	O
more	O
than	O
one	O
of	O
its	O
eight	O
processors	O
at	O
any	O
one	O
time	O
was	O
poor	O
.	O
</s>
<s>
It	O
is	O
a	O
mistake	O
to	O
believe	O
that	O
ETA	O
's	O
demise	O
was	O
based	O
solely	O
on	O
operating	B-General_Concept
system	I-General_Concept
choice	O
or	O
existence	O
.	O
</s>
<s>
The	O
Fortran	B-Application
compiler	O
(	O
ftn200	O
)	O
had	O
not	O
changed	O
from	O
the	O
CDC205	O
.	O
</s>
<s>
This	O
compiler	O
retained	O
vendor-specific	O
programming	O
performance	O
features	O
(	O
known	O
as	O
the	O
Q8*	O
subroutine	O
calls	O
)	O
in	O
an	O
era	O
when	O
supercomputer	B-Architecture
users	O
were	O
realizing	O
the	O
necessity	O
of	O
source	O
code	O
portability	O
between	O
architectures	O
.	O
</s>
<s>
Additionally	O
,	O
the	O
compiler	O
optimizations	O
were	O
not	O
keeping	O
up	O
with	O
existing	O
technology	O
as	O
shown	O
by	O
the	O
Japanese	O
supercomputer	B-Architecture
vendors	O
as	O
well	O
as	O
the	O
newer	O
minisupercomputer	O
makers	O
and	O
competition	O
at	O
Cray	O
Research	O
.	O
</s>
<s>
CDC	O
was	O
relatively	O
weak	O
in	O
this	O
area	O
,	O
and	O
some	O
of	O
the	O
best	O
operating	B-General_Concept
systems	I-General_Concept
that	O
CDC	O
provided	O
to	O
customers	O
were	O
productized	O
versions	O
of	O
an	O
OS	O
written	O
by	O
Lawrence	O
Livermore	O
Laboratories	O
.	O
</s>
<s>
There	O
were	O
four	O
models	O
of	O
the	O
ETA10	B-Operating_System
.	O
</s>
<s>
Any	O
of	O
these	O
models	O
could	O
be	O
built	O
in	O
either	O
single	O
-	O
or	O
multi-processor	B-Operating_System
configurations	O
.	O
</s>
<s>
The	O
Models	O
E	O
and	O
G	O
were	O
the	O
highest-performing	O
members	O
of	O
the	O
ETA10	B-Operating_System
line	O
,	O
and	O
used	O
liquid	O
nitrogen	O
cooling	O
to	O
achieve	O
rapid	O
cycle	O
times	O
.	O
</s>
<s>
Between	O
the	O
highest-performing	O
,	O
liquid-nitrogen	O
cooled	O
models	O
(	O
ETA10-E	O
,	O
G	O
,	O
etc	O
.	O
)	O
</s>
<s>
and	O
the	O
cheaper	O
,	O
air-cooled	O
models	O
(	O
ETA10-P	O
,	O
Q	O
,	O
etc	O
.	O
</s>
<s>
)	O
,	O
the	O
ETA10	B-Operating_System
line	O
spanned	O
a	O
27:1	O
performance	O
range	O
.	O
</s>
<s>
A	O
single-processor	O
ETA10	B-Operating_System
achieved	O
52MFLOPS	O
on	O
the	O
LINPACK	B-Application
benchmark	O
for	O
a	O
matrix	O
with	O
a	O
size	O
of	O
100×100	O
.	O
</s>
<s>
The	O
ETA10	B-Operating_System
was	O
a	O
multiprocessor	B-Operating_System
system	O
that	O
supported	O
up	O
to	O
eight	O
CPUs	O
.	O
</s>
<s>
Each	O
CPU	B-General_Concept
was	O
similar	O
to	O
that	O
of	O
a	O
two-lane	O
Cyber	B-Device
205	I-Device
.	O
</s>
<s>
One	O
of	O
the	O
main	O
innovations	O
of	O
the	O
ETA10	B-Operating_System
was	O
how	O
the	O
CPU	B-General_Concept
was	O
implemented	O
:	O
the	O
CPU	B-General_Concept
was	O
made	O
of	O
250	O
CMOS	B-Device
gate	O
array	O
integrated	O
circuits	O
mounted	O
on	O
a	O
44-layer	O
printed	O
circuit	O
board	O
(	O
PCB	O
)	O
.	O
</s>
<s>
CMOS	B-Device
circuitry	O
,	O
which	O
was	O
not	O
typically	O
used	O
in	O
vector	B-Operating_System
supercomputer	B-Architecture
CPUs	O
at	O
the	O
time	O
,	O
was	O
chosen	O
because	O
of	O
the	O
high	O
density	O
achievable	O
,	O
which	O
reduces	O
both	O
the	O
on-chip	O
and	O
off-chip	O
delay	O
.	O
</s>
<s>
The	O
CPU	B-General_Concept
delays	O
were	O
managed	O
through	O
careful	O
tuning	O
of	O
each	O
PCB	O
manufactured	O
in	O
conjunction	O
with	O
the	O
logic	O
technology	O
and	O
incorporated	O
two	O
key	O
technologies	O
known	O
as	O
JTAG	O
and	O
BIST	O
.	O
</s>
<s>
However	O
,	O
CMOS	B-Device
circuitry	O
at	O
that	O
time	O
was	O
significantly	O
slower	O
than	O
that	O
of	O
bipolar	O
circuitry	O
,	O
especially	O
the	O
emitter-coupled	B-General_Concept
logic	I-General_Concept
that	O
was	O
widely	O
used	O
in	O
vector	B-Operating_System
supercomputer	B-Architecture
CPUs	O
at	O
the	O
time	O
.	O
</s>
<s>
To	O
compensate	O
for	O
this	O
,	O
the	O
CPU	B-General_Concept
was	O
immersed	O
in	O
-196.15	O
°C	O
liquid	O
nitrogen	O
for	O
cooling	O
.	O
</s>
<s>
Although	O
such	O
cooling	O
could	O
potentially	O
speed	O
up	O
the	O
CMOS	B-Device
logic	O
by	O
a	O
factor	O
of	O
four	O
,	O
in	O
practice	O
the	O
liquid	O
nitrogen	O
cooling	O
yielded	O
an	O
approximately	O
twofold	O
speed	O
increase	O
over	O
air-cooled	O
systems	O
.	O
</s>
<s>
However	O
,	O
because	O
liquid	O
nitrogen	O
cooling	O
yielded	O
only	O
marginal	O
performance	O
benefits	O
,	O
none	O
of	O
the	O
ETA10	B-Operating_System
systems	O
used	O
such	O
cooling	O
for	O
either	O
the	O
local	O
or	O
shared	O
memories	O
.	O
</s>
<s>
Each	O
CPU	B-General_Concept
had	O
its	O
own	O
4	O
million	O
word	O
local	O
memory	O
built	O
from	O
SRAM	O
ICs	O
.	O
</s>
<s>
Each	O
CPU	B-General_Concept
is	O
also	O
connected	O
to	O
a	O
256	O
million	O
word	O
shared	O
memory	O
built	O
from	O
DRAM	O
ICs	O
.	O
</s>
<s>
In	O
addition	O
to	O
these	O
memories	O
,	O
there	O
is	O
a	O
communication	O
buffer	O
used	O
for	O
CPU	B-General_Concept
synchronization	O
and	O
other	O
multiprocessor-related	O
protocol	O
communication	O
.	O
</s>
<s>
The	O
ETA10	B-Operating_System
used	O
fiber-optic	B-Architecture
lines	O
for	O
communication	O
between	O
the	O
CPUs	O
and	O
I/O	O
devices	O
,	O
a	O
novel	O
approach	O
for	O
systems	O
interconnection	O
in	O
the	O
1980s	O
.	O
</s>
<s>
Purdue	O
University	O
(	O
contributed	O
to	O
ETA	O
System	B-Operating_System
V	I-Operating_System
,	O
the	O
System	B-Operating_System
V	I-Operating_System
UNIX	I-Operating_System
variant	O
that	O
ran	O
on	O
the	O
ETA10	B-Operating_System
)	O
.	O
</s>
<s>
By	O
the	O
end	O
of	O
the	O
1980s	O
,	O
the	O
remaining	O
ETA10	B-Operating_System
systems	O
were	O
donated	O
to	O
high	O
schools	O
through	O
a	O
computer	B-General_Concept
science	I-General_Concept
competition	O
,	O
SuperQuest	O
:	O
</s>
