The history of supercomputing goes back to the early 1920s in the United States
with the IBM tabulators at Columbia University and a series of computers at
Control Data Corporation, designed by Seymour Cray to use innovative designs
and parallelism to achieve superior computational peak performance. The CDC
6600, released in 1964, is generally considered the first supercomputer.
While the supercomputers of the 1980s used only a few processors, in the
1990s, machines with thousands of processors began to appear both in the
United States and in Japan, setting new computational performance records.
By the end of the 20th century, massively parallel supercomputers with
thousands of "off-the-shelf" processors similar to those found in personal
computers were constructed and broke through the teraflop computational
barrier. Progress in the first decade of the 21st
century was dramatic and supercomputers with over 60,000 processors appeared,
reaching petaflop performance levels. Beginnings: 1950s and 1960s
The term "Super Computing" was first used in the New York World in 1929 to
refer to large custom-built tabulators that IBM had made for Columbia
University. In 1957 a group of engineers left Sperry
Corporation to form Control Data Corporation in Minneapolis, MN. Seymour
Cray left Sperry a year later to join his colleagues at CDC. In 1960 Cray
completed the CDC 1604, one of the first solid state computers, and the fastest
computer in the world at a time when vacuum tubes were found in most large
computers. Around 1960 Cray decided to design a
computer that would be the fastest in the world by a large margin. After four
years of experimentation along with Jim Thornton, and Dean Roush and about 30
other engineers Cray completed the CDC 6600 in 1964. Cray switched from
germanium to silicon transistors, built by Fairchild Semiconductor, that used
the planar process. These did not have the drawbacks of the mesa silicon
transistors. He ran them very fast, and the speed of light restriction forced a
very compact design with severe overheating problems, which were solved
by introducing refrigeration, designed by Dean Roush. Given that the 6600
outran all computers of the time by about 10 times, it was dubbed a
supercomputer and defined the supercomputing market when one hundred
computers were sold at $8 million each. The 6600 gained speed by "farming out"
work to peripheral computing elements, freeing the CPU to process actual data.
The Minnesota FORTRAN compiler for the machine was developed by Liddiard and
Mundstock at the University of Minnesota and with it the 6600 could sustain 500
kiloflops on standard mathematical operations. In 1968 Cray completed the
CDC 7600, again the fastest computer in the world. At 36 MHz, the 7600 had about
three and a half times the clock speed of the 6600, but ran significantly
faster due to other technical innovations. They only sold about 50 of
the 7600s, not quite a failure. Cray left CDC in 1972 to form his own
company. Two years after his departure CDC delivered the STAR-100 which at 100
megaflops was three times the speed of the 7600. Along with the Texas
Instruments ASC, the STAR-100 was one of the first machines to use vector
processing - the idea having been inspired around 1964 by the APL
programming language. In 1956, a team at Manchester University
in the United Kingdom, began development of MUSE — a name derived from
microsecond engine — with the aim of eventually building a computer that
could operate at processing speeds approaching one microsecond per
instruction, about one million instructions per second. Mu is a prefix
in the SI and other systems of units denoting a factor of 10−6.
At the end of 1958 Ferranti agreed to begin to collaborate with Manchester
University on the project, and the computer was shortly afterwards renamed
Atlas, with the joint venture under the control of Tom Kilburn. The first Atlas
was officially commissioned on 7 December 1962, nearly three years after
the Cray CDC 6600 supercomputer was introduced, as one of the world's first
supercomputers - and was considered to be the most powerful computer in England
and for a very short time was considered to be one of the most powerful computers
in the world, and equivalent to four IBM 7094s. It was said that whenever
England's Atlas went offline half of the United Kingdom's computer capacity was
lost. The Atlas Computer pioneered the use of virtual memory and paging as a
way to extend the Atlas Computer's working memory by combining its 16
thousand words of primary core memory with an additional 96 thousand words of
secondary drum memory. Atlas also pioneered the Atlas Supervisor,
"considered by many to be the first recognizable modern operating system".
The Cray era: mid-1970s and 1980s Four years after leaving CDC, Cray
delivered the 80 MHz Cray 1 in 1976, and it became the most successful
supercomputer in history. The Cray 1 used integrated circuits with two gates
per chip and was a vector processor which introduced a number of innovations
such as chaining in which scalar and vector registers generate interim
results which can be used immediately, without additional memory references
which reduce computational speed. The Cray X-MP was released in 1982 as a 105
MHz shared-memory parallel vector processor with better chaining support
and multiple memory pipelines. All three floating point pipelines on the X-MP
could operate simultaneously. The Cray-2 released in 1985 was a 4
processor liquid cooled computer totally immersed in a tank of Fluorinert, which
bubbled as it operated. It could perform to 1.9 gigaflops and was the world's
fastest until 1990 when ETA-10G from CDC overtook it. The Cray 2 was a totally
new design and did not use chaining and had a high memory latency, but used much
pipelining and was ideal for problems that required large amounts of memory.
The software costs in developing a supercomputer should not be
underestimated, as evidenced by the fact that in the 1980s the cost for software
development at Cray came to equal what was spent on hardware. That trend was
partly responsible for a move away from the in-house, Cray Operating System to
UNICOS based on Unix. The Cray Y-MP, also designed by Steve
Chen, was released in 1988 as an improvement of the X-MP and could have
eight vector processors at 167 MHz with a peak performance of 333 megaflops per
processor. In the late 1980s, Cray's experiment on the use of gallium
arsenide semiconductors in the Cray-3 did not succeed. Cray began to work on a
massively parallel computer in the early 1990s, but died in a car accident in
1996 before it could be completed. Cray Research did, however, produce such
computers. Massive processing: the 1990s
The Cray-2 which set the frontiers of supercomputing in the mid to late 1980s
had only 8 processors. In the 1990s, supercomputers with thousands of
processors began to appear. Another development at the end of the 1980s was
the arrival of Japanese supercomputers, some of which were modeled after the
Cray-1. The SX-3/44R was announced by NEC
Corporation in 1989 and a year later earned the fastest in the world title
with a 4 processor model. However, Fujitsu's Numerical Wind Tunnel
supercomputer used 166 vector processors to gain the top spot in 1994. It had a
peak speed of 1.7 gigaflops per processor. The Hitachi SR2201 on the
other hand obtained a peak performance of 600 gigaflops in 1996 by using 2048
processors connected via a fast three-dimensional crossbar network.
In the same timeframe the Intel Paragon could have 1000 to 4000 Intel i860
processors in various configurations, and was ranked the fastest in the world
in 1993. The Paragon was a MIMD machine which connected processors via a high
speed two-dimensional mesh, allowing processes to execute on separate nodes;
communicating via the Message Passing Interface. By 1995 Cray was also
shipping massively parallel systems, e.g. the Cray T3E with over 2,000
processors, using a three-dimensional torus interconnect.
The Paragon architecture soon led to the Intel ASCI Red supercomputer in the
United States, which held the top supercomputing spot to the end of the
20th century as part of the Advanced Simulation and Computing Initiative.
This was also a mesh-based MIMD massively-parallel system with over
9,000 compute nodes and well over 12 terabytes of disk storage, but used
off-the-shelf Pentium Pro processors that could be found in everyday personal
computers. ASCI Red was the first system ever to break through the 1 teraflop
barrier on the MP-Linpack benchmark in 1996; eventually reaching 2 teraflops.
Petaflops computing in the 21st century Significant progress was made in the
first decade of the 21st century and it was shown that the power of a large
number of small processors can be harnessed to achieve high performance,
e.g. as in System X's use of 1,100 Apple Power Mac G5 computers quickly assembled
in the summer of 2003 to gain 12.25 teraflops.
The efficiency of supercomputers continued to increase, but not
dramatically so. The Cray C90 used 500 kilowatts of power in 1991, while by
2003 the ASCI Q used 3,000 kW while being 2,000 times faster, increasing the
performance per watt 300 fold. In 2004 the Earth Simulator
supercomputer built by NEC at the Japan Agency for Marine-Earth Science and
Technology reached 35.9 teraflops, using 640 nodes, each with eight proprietary
vector processing chips. The IBM Blue Gene supercomputer
architecture found widespread use in the early part of the 21st century, and 27
of the computers on the TOP500 list used that architecture. The Blue Gene
approach is somewhat different in that it trades processor speed for low power
consumption so that a larger number of processors can be used at air cooled
temperatures. It can use over 60,000 processors, with 2048 processors "per
rack", and connects them via a three-dimensional torus interconnect.
Progress in China has been rapid, in that China placed 51st on the TOP500
list in June 2003, then 14th in November 2003 and 10th in June 2004 and then 5th
during 2005, before gaining the top spot in 2010 with the 2.5 petaflop Tianhe-I
supercomputer. In July 2011 the 8.1 petaflop Japanese K
computer became the fastest in the world using over 60,000 commercial scalar
SPARC64 VIIIfx processors housed in over 600 cabinets. The fact that K computer
is over 60 times faster than the Earth Simulator, and that the Earth Simulator
ranks as the 68th system in the world 7 years after holding the top spot
demonstrates both the rapid increase in top performance and the widespread
growth of supercomputing technology worldwide.
Historical TOP500 table This is a list of the computers which
appeared at the top of the Top500 list since 1993. The "Peak speed" is given as
the "Rmax" rating. Export controls
The CoCom and its later replacement, the Wassenaar Arrangement, legally regulated
- required licensing and approval and record-keeping; or banned entirely - the
export of high-performance computers to certain countries. Such controls have
become harder to justify, leading to loosening of these regulations. Some
have argued these regulations were never justified.
See also Linpack
TOP500 Green 500
FLOPS Instructions per second
Quasi-opportunistic supercomputing Supercomputer architecture
Supercomputing in China Supercomputing in Europe
Supercomputing in India Supercomputing in Japan
Supercomputing in Pakistan References