A Chinese supercomputer is the fastest in the world, according to survey results announced Monday, comfortably overtaking a US machine which now ranks second.

Tianhe-2, a supercomputer developed by China's National University of Defense Technology, achieved processing speeds of 33.86 petaflops (1000 trillion calculations) per second on a benchmarking test, earning it the number one spot in the Top 500 survey of supercomputers.

The tests show the machine is by far the fastest computer ever constructed. Its main rival, the US-designed Titan, had achieved a performance of 17.59 petaflops per second, the survey's website said.

Five of the world's 10 fastest computers are installed in the US, the survey said, with the two in China, two in Germany and one in Japan.

The recognition of Tianhe-2, meaning Milky Way-2, as the world's fastest computer marks the return of the title to China after the machine's predecessor, the Tianhe-1 was ranked the world's fastest in November 2010, only to be overtaken by a machine from the US.

Unlike some of its Chinese predecessors, most of the Tianhe-2's parts are developed in China, except for its main processors, which are designed by US firm Intel.

"Most of the features of the system were developed in China...the interconnect, operating system, front-end processors and software are mainly Chinese," the list's website quoted editor Jack Dongarra as saying.

But the US still dominates the overall supercomputer rankings, with 252 systems making the top 500. The number of European machines, at 112 systems remains lower than the number of Asian machines, at 119, the list's website said.

The supercomputers on the Top 500 list, which is produced twice a year, are rated based on speed of performance in a benchmark test by experts from Germany and the United States.