The history of machine computing started with mechanical computers which used gears, levers, curved plates etc. to perform calculations. The mechanical computers were typically single-purpose machines and could not be programmed in the modern sense. In addition to the standard desk calculators, typical examples were the devices used in aiming bombs, guns and torpedoes during World War II. However, programmable motor-driven mechanical machines such as Z1 were also developed.
The mechanical computers were succeeded by electro-mechanical machines which used switches and relays to implement logic.
ENIAC (Electronic Numerical Integrator and Computer), which became operational in 1945, was the first fully electronic programmable general-purpose computer and can be considered the first supercomputer. Originally constructed for calculating artillery shell and missile trajectories, it was located at the University of Pennsylvania and contributed to the US thermonuclear weapons development.
ENIAC relied on vacuum tubes, and its performance (about 400 flops or floating point operations per second) was in the order of one thousand times greater than the preceding electro-mechanical computers. ENIAC was a decimal (as opposed to modern binary) computer and was programmed by changing the configuration of the system by turning dials and plugging cables to receptables.
ENIAC and its vacuum-tubed successors were followed by transistorized systems in the latter half of the 1950's. IBM's 7090 mainframe (first installation in 1959) was specifically designed for solving large-scale scientific and engineering problems.
The term supercomputing was first used in 1964 when Control Data Corporation introduced the CDC 6600 system designed by Seymour Cray, whose name went on to became synonymous with supercomputers. An improved version, called CDC 6700, was introduced in 1969. Cray subsequently left Control Data Corporation, founded a company of his own, and in 1976 debuted the iconic Cray-1 supercomputer.
Parallel computers were investigated already in the 1960s, but until the late 1980s most supercomputers employed only a single, or at most a few processors. The processors used were also often designed specifically for supercomputers. As an example, Cray Y-MP introduced in 1989 had eight special vector processors. During the 1990s supercomputers started to be based more on commodity processors (such as Intel x86) and massively parallel processing. An important landmark in 1995 was the Beowulf cluster, which was built from commodity-grade components (Intel DX4 processors and Ethernet network) and running the Linux operating system. Nowadays, most supercomputers are based on commodity processors, but the network connecting the processors is typically designed specifically for supercomputers.
Supercomputer performance in the past has followed Moore's law steadily. In its original formulation (by Gordon Moore, founder of Intel), Moore's law states that the density of the transistors in an integrated circuit doubles every two years, implying that the performance also doubles. For a long time, the clock frequency of processors, i.e. the speed on which they operate, increased constantly. However, since the power consumed by a processor (and thus the heat it generates) increases with the third power of the clock frequency, clock frequencies have stagnated since around 2005. Since then, performance has been increased by adding multiple cores to a single CPU (multicore CPUs are nowaways ubiquitous in all devices from smart phones to supercomputers), and in the case of a supercomputer by adding more and more multicore CPUs to the same computer. As a result, the performance of supercomputers has kept on doubling every two years.
Nowadays, a supercomputer is often defined as a computer that has much larger computing power than a typical desktop computer. This is naturaly a moving definition; as also the performance of desktop computers has increased, a modern laptop is 1000 times more powerful than the biggest supercomputer in the Nordic countries thirty years ago.
In addition to Cray (now a product line of HPE), the most common names of the supercomputer vendors include IBM, SGI/Silicon Graphics, Hewlett-Packard, Atos, Dell, Intel, Fujitsu, Lenovo and Sun.
CSC's (Center for Scientific Computing) history can be traced back to 1971 when a special office was founded to operate a Univac 1108 system. There have since been a number of changes to the name, the organization and the owner of the entity that was tasked with operating the Finnish high-performance computing resources for scientists. In the 1990's, the name CSC was introduced, and the Ministry of Education and Culture became the sole owner of the company. Today, universities and polytechnics own a minor share of CSC – IT Center for Science Ltd.
CSC and its predecessors have operated the following major systems in Finland:
- Univac 1108 1971–1982
- Univac 1100/61 1982–1985
- VAX 8600 1985
- Cray X-MP 1989 The 'purple top-hat'. Vector processor.
- Cray C94 1995 The last vector processor machine at CSC.
- Cray T3E 1996–2002 The first MPP (massively parallel processor) system in Finland. 540 375 MHz DEC Alpha EV56 processors, 128 MB memory per node. 3D torus interconnect. Liquid-cooled. Theoretical peak performance 405 Gflop/s.
- IBM p690 2002–2005 16 loosely connected islands with 32 1,1 GHz Power4 processors. 512 processors in total, 32–64 GB memory per processor. Theoretical peak performance 2253 Gflop/s.
- Cray XT4/XT5 2007–2012 MPP system with dual 2,3 GHz AMD Opteron quad core processors and 8 GB memory per node. 10864 cores in total. 3D torus interconnect. Air-cooled. Theoretical peak performance 102 Tflop/s. Power 520 kW.
- Cray XC40 2012–2019 MPP system with dual 2,6 GHz Intel Xeon 12 core processors and 64 GB memory per node. 40512 cores in total. 3D torus interconnect. Liquid-cooled. Theoretical peak performance 1690 Tflop/s. Power 680 kW.
- Bull XH2000 2020 2020– MPP system with dual 2,6 GHz AMD Rome 128 core processors and 256 GB memory per node. 169728 cores in total. Dragonfly+ interconnect. Liquid-cooled. Theoretical peak performance 7061 Tflop/s. Power 1070 kW.
There have also been a number of supporting systems.
The graphs above depict the performance of selected CSC supercomputers from 1993-2020. The top graph shows the computing capacity of each given system with units being standardized processors. Note that the top graph is logarithmic, meaning that the growth is exponential not linear.
The bottom graph depicts the ranking of these systems on the top 500 rating. Each line shows how that system drops rank throughout the years. As of 2020 the latest CSC system was still in the top 50 ranking.