The Tianhe-2, a supercomputer developed by China's National University of Defense Technology, was named the world's top supercomputer for the fourth consecutive time by the TOP500 project. [Photo/Xinhua]

The Tianhe-2, a supercomputer developed by China's National University of Defense Technology, was named the world's top supercomputer for the fourth consecutive time by the TOP500 project.

The Tianhe-2 relegated the US-developed Titan to second spot with a performance of 33.86 petaflop (quadrillions of calculations per second) in a standardized test designed to measure computer performance.

IBM's Sequoia rounded out the top 3 in the TOP500 list.

The TOP500 project, started in 1993, issues a list twice a year that ranks supercomputers based on their performance.

There was little change in the top 10 in the latest list and the only new entry was at number 10 – the Cray CS-Storm, developed by Cray Inc, which also developed the Titan.

The United States was home to six of the top 10 supercomputers, while China, Japan, Switzerland and Germany had one entrant each.

The United States remained the top country in terms of overall systems with 231, down from 233 in June and falling near its historical low.

The number of Chinese systems on the list also dropped to 61 from 76 in June, while Japan increased its number of systems from 30 to 32.