The K computer named for the Japanese word/numeral , meaning 10

quadrillion Two naming scales for large numbers have been used in English and other European languages since the early modern era: the long and short scales. Most English variants use the short scale today, but the long scale remains dominant in many non-E ...

(10¹⁶)See

Japanese numbers The Japanese numerals are the number names used in Japanese. In writing, they are the same as the Chinese numerals, and large numbers follow the Chinese style of grouping by 10,000. Two pronunciations are used: the Sino-Japanese (on'yomi) reading ...

was a

supercomputer A supercomputer is a computer with a high level of performance as compared to a general-purpose computer. The performance of a supercomputer is commonly measured in floating-point operations per second ( FLOPS) instead of million instructio ...

manufactured by

Fujitsu is a Japanese multinational information and communications technology equipment and services corporation, established in 1935 and headquartered in Tokyo. Fujitsu is the world's sixth-largest IT services provider by annual revenue, and the la ...

, installed at the Riken Advanced Institute for Computational Science campus in

Kobe Kobe ( , ; officially , ) is the capital city of Hyōgo Prefecture Japan. With a population around 1.5 million, Kobe is Japan's seventh-largest city and the third-largest port city after Tokyo and Yokohama. It is located in Kansai region, whi ...

Hyōgo Prefecture is a prefecture of Japan located in the Kansai region of Honshu. Hyōgo Prefecture has a population of 5,469,762 () and has a geographic area of . Hyōgo Prefecture borders Kyoto Prefecture to the east, Osaka Prefecture to the southeast, an ...

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the n ...

. The K computer was based on a

distributed memory In computer science, distributed memory refers to a multiprocessor computer system in which each processor has its own private memory. Computational tasks can only operate on local data, and if remote data are required, the computational task mu ...

architecture with over 80,000 compute nodes. It was used for a variety of applications, including climate research, disaster prevention and medical research. The K computer's

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ef ...

was based on the

Linux kernel The Linux kernel is a free and open-source, monolithic, modular, multitasking, Unix-like operating system kernel. It was originally authored in 1991 by Linus Torvalds for his i386-based PC, and it was soon adopted as the kernel for the GNU ...

, with additional drivers designed to make use of the computer's hardware. In June 2011,

TOP500 The TOP500 project ranks and details the 500 most powerful non- distributed computer systems in the world. The project was started in 1993 and publishes an updated list of the supercomputers twice a year. The first of these updates always coinci ...

ranked K the world's fastest supercomputer, with a computation speed of over 8 petaflops, and in November 2011, K became the first computer to top 10 petaflops.June 2011 TOP500 Supercomputer Sites
/ref> It had originally been slated for completion in June 2012. In June 2012, K was superseded as the world's fastest supercomputer by the American IBM Sequoia. , the K computer holds the third place for the

HPCG benchmark The HPCG (high performance conjugate gradient) benchmark is a supercomputing benchmark test proposed by Michael Heroux from Sandia National Laboratories, and Jack Dongarra and Piotr Luszczek from the University of Tennessee. It is intended to model ...

. It held the first place until June 2018, when it was superseded by

Summit A summit is a point on a surface that is higher in elevation than all points immediately adjacent to it. The topographic terms acme, apex, peak (mountain peak), and zenith are synonymous. The term (mountain top) is generally used only for a m ...

and Sierra. , K is the world's 20th-fastest computer, with the IBM's Summit and Sierra being the fastest supercomputers. The K supercomputer was decommissioned on 30 August 2019. In Japan, the K computer was succeeded by the Fugaku supercomputer, in 2020, which took the top spot, and is three times faster than 2nd most powerful supercomputer.

Performance

On 20 June 2011, the

Project Committee announced that K had set a LINPACK record with a performance of 8.162 petaflops, making it the fastest supercomputer in the world at the time; it achieved this performance with a computing efficiency ratio of 93.0%. The previous record holder was the Chinese

National University of Defense Technology The National University of Defense Technology (NUDT; ) is a national public research university in Changsha, Hunan, China. Founded in 1953 as the People's Liberation Army Military Academy of Engineering, the institution is directly affilia ...

Tianhe-1A Tianhe-I, Tianhe-1, or TH-1 (, ; '' Sky River Number One'') is a supercomputer capable of an Rmax (maximum range) of 2.5 peta FLOPS. Located at the National Supercomputing Center of Tianjin, China, it was the fastest computer in the world ...

, which performed at 2.507 petaflops. The TOP500 list is revised semiannually, and the rankings change frequently, indicating the speed at which computing power is increasing. In November 2011, Riken reported that K had become the first supercomputer to exceed 10 petaflops, achieving a LINPACK performance of 10.51 quadrillion computations per second with a computing efficiency ratio of 93.2%."K computer" Achieves Goal of 10 Petaflops"
Fujitsu. 2 November 2011. Retrieved 10 November. 2011. K received top ranking in all four performance benchmarks at the 2011 HPC Challenge Awards. On 18 June 2012, the TOP500 Project Committee announced that the

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

-based IBM Sequoia supercomputer replaced K as the world's fastest supercomputer, with a LINPACK performance of 16.325 petaflops. Sequoia is 55% faster than K, using 123% more CPU processors, but is also 150% more energy efficient. On the TOP500 list, it became first in June 2011, falling down through time to lower positions, to eighteenth in November 2018. K computer holds third place in the

test proposed by

Jack Dongarra Jack Joseph Dongarra (born July 18, 1950) is an American computer scientist and mathematician. He is the American University Distinguished Professor of Computer Science in the Electrical Engineering and Computer Science Department at the Unive ...

, with 0.6027 HPCG PFLOPS in November 2018.

Specifications

Node architecture

The K computer comprises 88,128 2.0 GHz eight-core

SPARC64 VIIIfx The SPARC64 V (''Zeus'') is a SPARC V9 microprocessor designed by Fujitsu. The SPARC64 V was the basis for a series of successive processors designed for servers, and later, supercomputers. The servers series are the SPARC64 V+, VI, VI+, VII, V ...

processor Processor may refer to: Computing Hardware * Processor (computing) **Central processing unit (CPU), the hardware within a computer that executes a program *** Microprocessor, a central processing unit contained on a single integrated circuit (I ...

s contained in 864 cabinets, for a total of 705,024 cores, manufactured by Fujitsu with

45 nm Per the International Technology Roadmap for Semiconductors, the 45 nm process is a MOSFET technology node referring to the average half-pitch of a memory cell manufactured at around the 2007–2008 time frame. Matsushita and Intel started mass ...

CMOS Complementary metal–oxide–semiconductor (CMOS, pronounced "sea-moss", ) is a type of metal–oxide–semiconductor field-effect transistor (MOSFET) fabrication process that uses complementary and symmetrical pairs of p-type and n-type MOSF ...

technology. Each cabinet contains 96 computing nodes, in addition to six I/O nodes. Each computing node contains a single processor and 16 GB of memory. The computer's

water cooling Cooling tower and water discharge of a nuclear power plant Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and non ...

system is designed to minimize

failure rate Failure rate is the frequency with which an engineered system or component fails, expressed in failures per unit of time. It is usually denoted by the Greek letter λ (lambda) and is often used in reliability engineering. The failure rate of a ...

and

power consumption Electric energy consumption is the form of energy consumption that uses electrical energy. Electric energy consumption is the actual energy demand made on existing electricity supply for transportation, residential, industrial, commercial, and ot ...

Network

The nodes are connected by Fujitsu's proprietary

torus fusion Torus fusion (tofu) is a proprietary computer network topology for supercomputers developed by Fujitsu. It is a variant of the torus interconnect. The system has been used in the K computer and the Fugaku supercomputer (and their derivatives). Tof ...

(''Tofu'') interconnect.

File system

The system adopts a two-level local/global

file system In computing, file system or filesystem (often abbreviated to fs) is a method and data structure that the operating system uses to control how data is stored and retrieved. Without a file system, data placed in a storage medium would be one larg ...

with parallel/distributed functions, and provides users with an automatic

staging Staging may refer to: Computing * Staging (cloud computing), a process used to assemble, test, and review a new solution before it is moved into production and the existing solution is decommissioned * Staging (data), intermediately storing data b ...

function for moving files between global and local file systems. Fujitsu developed an optimized parallel file system based on Lustre, called the Fujitsu Exabyte File System (FEFS), which is scalable to several hundred petabytes.

Power consumption

Although the K computer reported the highest total power consumption of any 2011 TOP500 supercomputer (9.89 MW the equivalent of almost 10,000 suburban homes), it is relatively efficient, achieving 824.6 GFlop/kW. This is 29.8% more efficient than China's NUDT TH MPP (ranked #2 in 2011), and 225.8% more efficient than Oak Ridge's Jaguar-Cray XT5-HE (ranked #3 in 2011). However, K's power efficiency still falls far short of the 2097.2 GFlops/kWatt supercomputer record set by IBM's NNSA/SC Blue Gene/Q Prototype 2. For comparison, the average power consumption of a TOP 10 system in 2011 was 4.3 MW, and the average efficiency was 463.7 GFlop/kW. According to TOP500 compiler

, professor of electrical engineering and computer science at the

University of Tennessee The University of Tennessee (officially The University of Tennessee, Knoxville; or UT Knoxville; UTK; or UT) is a public land-grant research university in Knoxville, Tennessee. Founded in 1794, two years before Tennessee became the 16th sta ...

, the K computer's performance equals "one million linked desktop computers". The computer's annual running costs are estimated at US$10 million.

K Computer Mae rapid transit station

On 1 July 2011,

Port Island Line The , commonly known as is an urban automated guideway transit (AGT) system in Kobe, Japan, operated by Kobe New Transit. Opened in 1981, the Port Liner was the world's first driverless urban transit system, a few years ahead of the VAL syste ...

rapid transit Rapid transit or mass rapid transit (MRT), also known as heavy rail or metro, is a type of high-capacity public transport generally found in urban areas. A rapid transit system that primarily or traditionally runs below the surface may be ...

system renamed one of its stations from "Port Island Minami" to "K Computer Mae" (meaning "In front of K Computer") denoting its vicinity.

Notes

References

External links

Riken Advanced Institute for Computational ScienceK computer: Fujitsu Global
*[https://web.archive.org/web/20120311072800/http://www.riken.go.jp/engn/r-world/info/release/news/2006/apr/index.html#frol_01 Special Interview: Taking on the Challenge of a 10-Petaflop Computer, Riken News, No. 298, April 2006.]
June 2017 Top 500
{{DEFAULTSORT:K computer 2011 in science Fujitsu supercomputers One-of-a-kind computers Petascale computers Riken SPARC microprocessor products Supercomputing in Japan 64-bit computers