China's Sunway TaihuLight and Tianhe-2 are still the world's fastest and second fastest machines, but America's Titan was squeezed into fourth place by an upgraded Swiss system, according to the latest edition of the semiannual T0P500 list of supercomputers released Monday.

Sunway TaihuLight, described by the T0P500 list as "far and away the most powerful number-cruncher on the planet," maintained the lead since last June, when it dethroned Tianhe-2, the former champion for the previous three consecutive years.

It means that a Chinese supercomputer has topped the rankings maintained by researchers in the United States and Germany for nine times in a row.

What's more, Sunway TaihuLight, with a performance of 93 petaflops, was built entirely using processors designed and made in China.

"It highlights China's ability to conduct independent research in the supercomputing field," Haohuan Fu, deputy director of the National Supercomputing Center, where Sunway TaihuLight was installed, told Xinhua.

"China is simultaneously developing hardware and software technologies of supercomputers," Fu said. "It is expected that rapid development in homegrown hardware technologies, supported by homegrown software, will lead to a stronger research and engineering test capacity in many fields, thus promoting an industrial upgrading and, eventually, a sustainable development of China's homegrown supercomputing industry."

Tianhe-2, capable of performing 33.9 petaflops, was based on Intel chips, something banned by the U.S. government from selling to four supercomputing institutions in China since 2015.

In the latest rankings, the new number three supercomputer is the upgraded Piz Daint, a system installed at the Swiss National Supercomputing Center.

Its current performance of 19.6 petaflops pushed Titan, a machine installed at the U.S. Oak Ridge National Laboratory, into fourth place. Titan's performance of 17.6 petaflops has remained constant since it was installed in 2012.

"This is the second time in the 24-year history of the TOP500 list that the United States has failed to secure any of the top three positions," the TOP500 organizers said in a statement.

The only other time this occurred was in November 1996, when three Japanese systems captured the top three spots.

"Nevertheless, the U.S. still claims five of the top 10 supercomputers, which is more than any other nation," they said.

Fu called the upgraded Swiss system "really a surprise," saying that "it reflects the increased investment in large-scale supercomputers in Europe."