The Indian 'blip' on the global supercomputing scene has become somewhat bigger.

India has been able to regain lost ground in the supercomputing domain in recent years, with more of its machines making it to a reputed list that periodically ranks the top 500 supercomputers in the world, even as China leads the race in Asia with the maxiumum number of deployments of such machines.

If one were go by the latest 'TOP500' list, 11 of the top 500 supercomputers in the world are located in India. The list was released last month at the opening session of the 2013 International Supercomputing Conference in Leipzig, Germany.

But only 6 of these figure in the latest (June) version of a list of Indian supercomputers, the compilation of which is co-ordinated by Sathish Vadhiyar, associate professor, Supercomputer Education and Research Centre, Indian Institute of Science, Bangalore.

The most powerful supercomputer in the world, according to the top 500 list, has a speed of 33,862.7 teraflops (a teraflop is equal to one trillion calculations per second) on a technical benchmark called Linpack. Tianhe-2, belonging to China’s National University of Defense Technology, will be deployed at the National Supercomputer Center in Guangzho by the year end. It will mark China’s return to the top position since November 2010, when Tianhe-1A had topped the 500 list.

India' s most powerful system is one deployed by the Indian Institute of Tropical Meteorology, Pune, with its benchmarked performance touching 719.2 teraflops. Ranked second with a speed of 386.7 terfalops is PARAM Yuva - II, unveiled by Centre for Development of Advanced Computing, Pune, earlier this year.

The 'mismatch' between rankings in the Indian top supercomputers list and the global one is because anonymous entries do not find a place in the former, explained Dr Vadhiyar. The global list has also sometimes allowed entries based on the projected performance of the Linpack benchmark, while the Indian one is based on actual performance.

When the the Top 500 list is restricted to Indian systems, the sixth position, and the eigth to eleventh positions are occupied by supercomputers identified as those owned by manufacturing , semiconductor and network companies. They have speeds ranging from 149.2 to 104.2 teraflops. In the Indian list, these positions are occupied by less powerful systems.

But one significant development is that progressively more supercomputers from India are making it to the top 500 list, recovering from a situation in November 2011 where only a couple of its machines had figured in it.

Another development is that the number of Indian cities having supercomputers has been increasing in recent years, Dr Vadhiyar said. Bangalore leads the list with 8 of them. And as many as 11 systems have been added to the Indian list compared to its previous version released in December 2012 - the largest increase since it was first conceived in November 2008. And during this period combined supercomputing capability of the nation has increased by more than 1.5 petaflops to total 2.63 petaflops now (a petaflop is equal to 1,000 trillion calculations per second).

And overall, China now is right behind the United States in terms of supercomputing prowess in the world, ahead of other countries like Japan, UK, France, and Germany - between 66 and 75 supercomputers in the last 3 lists were from China. The United States accounts for as many as 252 of the 500 supercomputers in the latest list. Though India is ranked seventh in this list, it has ambitious plans to overtake other countries in the high performance computing race in the coming years.

On the top500.org website, the list's editor Jack Dongarra commented, “Most of the features of the system (Tianhe-2) were developed in China, and they are only using Intel for the main compute part. That is, the interconnect, operating system, front-end processors and software are mainly Chinese.”

One other development is that more and more computers in the list are crossing the petaflop range in terms of performance. This time there were 26 such systems, compared to 23, six months ago.