Weapons this is to ensure the operation now

It is a monster. With numbers that give the Vertigo. Tera 100, installed the very discrete management (DAM) military applications of Atomic Energy (CEA) Commissioner premises at Bruyères-le-Châtel (Essonne), is it only a piece of 600 square metres. Same démesure-side performance. His memory of 300 terabytes is equivalent to that of 150,000 computers developed end-to-Office, and its disks, which can host up to 20 petabytes, would store 25 billion pounds. For capacity calculation, it is 1.25 petaflop is 1.25 million billion operations per second. What the CEA summarized by a striking image: "This is the world's population would in 48 hours, at an operation per second and per person." More impressive, the flow circulates information between memory and disks at the breathtaking speed of 500 gigabytes per second. A world record. This stream of data, which is equivalent to 1 million people watching a film in high definition, is very important, ensures Jean Gonnord, head of the numerical simulation to the CEA DAM project: "A supercomputer deals with billions of data that must be stored quickly without threatening the calculation time." Tera 100 is able to transfer all of his memory on disk every hour in under five minutes. It is a world record.

Strategic interest

But the "beast" designed by Bull in collaboration with the ECA especially has a very strategic interest. Because the Tera 100 is to simulate the operation of nuclear weapons. Small back: in 1996, the France, more and more poorly seen in the world, stop its underground fire after signing the comprehensive nuclear test ban treaty. Engineers of the ECA then provide to the head of State that it is possible to replace the actual test by the computer simulation. To complete this program, entitled "simulation", it is establishing a team of 300 people from very high level. Their goal: develop a simulation software and buy computers to turn. Of course, the simulation is already existed. "Prior to 1996, we use already calculation codes which are then checked with the actual test results." We proceed by roundtrips between testing and simulation. "It is the first time claimed to guarantee the functioning of a complex object without any real experience", assures Jean Gonnord, one of the fathers of the project.

However, the work are huge. So need more rewriting existing software, which had been developed for older technology of supercomputers, vector computers. In the end, this huge simulation software, whose very name secret rest, has millions of lines of code and required 1,500 man years of work. With point focus the year 2015: to this date, current weapons will be put to the disposal, and nuclear submarines embarqueront of new atomic warheads. Weapons this is to ensure the operation now.

Technology challenge

The design of the supercomputer loaded to run the software was assigned to Bull, winner of the tender, in collaboration with the ECA. Tera 1 has seen in 2001 and 10 in 2005 Tera. From the outset, Bull left the principle to be, as in the world of the PC, buy components: processor, memory, and disks. The comparison ends there, both the complexity of these supercomputers so-called "massively parallel" is great. Thus, Tera 100, twenty times more potent than its predecessor, contrasts some computers 4.300 each with four Intel processors. "We have made many software development to optimize the operation." Thus, while Intel can operate together 8 processors, we're going up to 16 sharing 14 terabytes of memory. "What makes this unique machine", insists Pascal Barbolosi, Vice President of "extreme computing" in Bull.

The other challenge was that of energy consumption. "What was once trivial now represents a significant challenge." "The simple power is double the cost of ownership over five years," insists Jean Gonnord. And again, the ECA engineers and those of Bull have made considerable efforts to limit this consumption, with for example a same footprint on the ground than its predecessor. Good news, energy efficiency has increased by 7. Less good news, the monster eats to turn its processors - but also cooling - a power of 7 to 8 megawatts, equivalent to several hundreds of housing units.

In the constructor, the range of the Tera was named Bullx and received the trophy for the best magazine "hpc wire" supercomputer. Bull hopes to assume part of the market of supercalcultateurs, which the Europeans are absent and on which the Americans (with IBM, HP, SGI) and Japanese (with Hitachi, Fujitsu and NEC) are the law. The Chinese also embarked on the race with, most importantly, their own processors. 3 Billion dollars in 2007 market which should rise to 5 billion in 2012, according to IDC. Bull, which notably sold a machine at the UK Atomic Weapons (the British equivalent of the ECA), has achieved a turnover of 100 million euros last year and is an increase of 50 this year.