Photo/Illutration Supercomputer Fugaku, planned to be fully operational in fiscal 2021, on June 16 in Kobe (Jin Nishioka)

Japanese supercomputer Fugaku--named after Mount Fuji, Japan's tallest peak--has scaled new heights as the world's fastest supercomputer.

Fugaku ranked No. 1 in the world on June 22 in calculation speed, marking the first time in nine years that a Japanese supercomputer has headed the world ranking since its predecessor, K.

Fugaku, jointly developed by the Riken research institute and leading computer maker Fujitsu Ltd., rose to the top of the Top 500, a benchmark that measures the calculation speed of supercomputers, even though its creators prioritized user-friendliness over sheer speed. 

In the announcement of the latest list, Fugaku’s calculation speed was revealed as 416 quadrillion calculations per second, more than twice the speed of a supercomputer made in the United States that topped the ranking until last year.

Fugaku placed No. 1 in four of the categories, including the speed when software is running on it and the calculation speed for artificial intelligence (AI) applications.

Since the development of its predecessor K was focused too much on becoming the world’s No. 1, it was difficult to handle and failed to be widely used. Learning lessons from its development, creators of Fugaku aimed to make the only supercomputer that is easy to use.

The supercomputer was named after another name for Mount Fuji because the height of the mountain represents the high capabilities of the machine, and the wide areas of the base of the mountain show that a wide range of people can use it.

Government funding for the development of Fugaku alone reached 110 billion yen ($1.02 billion). The supercomputer ranked the world’s No. 1 due partly to China’s failure to enter the competition with a new model with a performance twice that of Fugaku, which the country sought to introduce at this year’s race.

Fugaku will go into full-scale operation in the next fiscal year that starts in April, but it has already made achievements in research on measures against novel coronavirus infections. The supercomputer will be used in discovering new drugs, developing high-performance materials and predicting weather and global warming.

Since high-performance computers can bring about innovations, such as enabling automakers to check the collision safety of cars before assembling them, it is hoped Fugaku will accelerate advancements in manufacturing as well as science and technology.

Supercomputers are also vital for the military, so China and the United States are fiercely competing in their development. The United States plans to enter the Top 500 competition in 2021 with a supercomputer that outperforms Fugaku.

“Countries continue to compete for becoming the world’s No. 1,” said Satoshi Matsuoka, director of the Riken Center for Computational Science (R-CCS) and also leader of the Fugaku development team. “We want to keep research in developing supercomputers that are both user friendly and high speed.”


Matsuoka praised his team’s achievements, saying, “(We spent) 10 years after the initial concept (of Fugaku) was proposed. We are very happy that it has shown itself to be outstanding (in performance in the world).”

A group of supercomputer researchers started releasing the Top 500 list in 1993. Initially, Japan and the United States competed for the top spot in the ranking, which is announced every June and November.

In 2002, for example, Japan’s Earth Simulator, developed by NEC Corp., topped the ranking, sending shock waves around the United States because it was five times faster than the second-place U.S. supercomputer. The level of surprise is said to rival the shock when the former Soviet Union went ahead of the United States in the early years of the space race.

However, Japan quickly lost its presence in the global supercomputer competition as the United States attempted to regain the top spot and China also started the development of supercomputers in full swing.

Fugaku’s predecessor K sought to become the world’s No. 1, but was criticized for its extremely high development cost. The development of the K computer was also thrown into disarray as major companies stopped developing it, making it the target of the budget screening process by the government, headed by the then ruling Democratic Party of Japan.

“Isn’t being No. 2 good enough?” said Renho, who was a lawmaker of the party at the time, about the K computer.

The K computer did manage to rise to No. 1 in the world, but it failed to be widely used because it was deemed unfriendly to users. Sales of supercomputers developed for consumer use by customizing the K computer did not go well at all, either.

“It’s like we made a state-of-the-art smartphone, but there are no apps available for the device,” said a science ministry official. “The private sector also turned its back on the development of supercomputers, causing it to be highly evolved but only useful in Japan.”

Against this backdrop, the creators of Fugaku aimed to make the world's only easy-to-use supercomputer. They enabled presentation software for ordinary computers to run on the supercomputer so that automakers and life science researchers can use the Fugaku in a casual manner.

The development team also equipped the supercomputer with functions necessary to use AI, which processes massive amounts of data, and deep learning.

The team also improved the energy efficiency of Fugaku, which has a 100 times higher performance than its predecessor and yet only two to three times greater power consumption than the K computer. A trial version of Fugaku placed No. 1 in the world for energy efficiency among supercomputers last autumn.

It was unusual for supercomputers for general use that are not designed to focus on energy efficiency to top the ranking.

“It’s like a car designed for highly practical use beat a supercar in performance,” said Matsuoka.


In addition to the speed of simple calculations, Fugaku also ranked as the world’s No. 1 in categories for big data analytics and the speed when software is running on it. It was reportedly the first time one supercomputer placed at the top in the three categories.

Installation of Fugaku at the R-CCS in Kobe was completed on May 13, two weeks before the deadline for entering the Top 500 ranking competition. Although a supercomputer usually is not functioning soon after its installation, technicians ultimately succeeded in operating 90 percent of Fugaku’s functions even during the state of emergency over the COVID-19 pandemic.

The supercomputer will be put into full-scale operation in the next fiscal year, but it has already been used in research on measures against the novel coronavirus outbreak, such as simulating how droplets containing the virus spread and efficiently ventilating train cars. Search for a drug to treat COVID-19 patients has also started.

Fugaku is also making commercial achievements since a supercomputer for consumers using the same CPU as Fugaku’s and delivered to Nagoya University ranked 37th in the latest Top 500 ranking. A U.S. company adopted the CPU for its own supercomputer and universities and research institutes in Europe and the United States also reportedly decided to introduce the CPU.

However, the United States, China and European countries are expected to enter the competition with multiple supercomputers that are superior to Fugaku in the future. There are many issues Japan needs to address, including whether the country should accelerate the current pace of developing one massive supercomputer per decade.

(This article was written by Nami Sugiura, Tetsuya Ishikura and Hisatoshi Kabata.)