China loses ground in top supercomputer list

The second most powerful supercomputer in the world, Sierra, is owned by the US Department of Energy

China has fallen behind slightly in the list of the world's top 500 supercomputers, which is published every six months.

The US maintained its position, holding first and second place with the two most powerful computers in the world.

At number one is Summit, with peak processing power of 200 petaflops - 200 quadrillion calculations per second.

The number of US supercomputers within the 500 has increased since November, from 109 to 116.

China retains the most entrants in the list, however. Its tally fell from 227 to 219.

The Top500 tracks the processing power of the world's fastest supercomputers, which are used to accomplish a wide range of tasks - from designing jet engines to training neural networks.

The top three supercomputers, in order, are:

• Summit, at the US Department of Energy - built by IBM

• Sierra, at the US Department of Energy - built by IBM

• Sunway TaihuLight, at the Chinese National Supercomputing Center - built by NRCPC

The latest list features, for the first time, only supercomputers with at least one petaflop of processing power - that equates to a quadrillion calculations per second.

The total combined power of all 500 supercomputers in the list comes to 1.56 exaflops - or one and a half quintillion calculations per second.

That is an increase of 10% from six months ago, when the combined processing power reached 1.41 exaflops.

One exaflop is roughly equivalent to every human on Earth doing calculation per second, for four years.

The combined power of the Top500 could more than double in 2021, as the US is expected to fire up two new supercomputers, Frontier and Aurora, which each pack at least one exaflop.

Other nations are represented in the list. The UK has 18 supercomputers in the top 500, the same number as France. Japan has one more, at 19, and Germany has 14.