IBM's Roadrunner is top of the supercomputer pops

So IBM beat IBM in the new supercomputer TOP500 hit parade published today. No surprise there, with Roadrunner, the new no.1, built by IBM for the Los Alamos National Laboratory, earning plenty of airtime last week for being the first petaflop computer.

Reduced to no.2 is IBM's BlueGene/L (478.2 teraflop/s) at the US Department of Energy's Lawrence Livermore National Laboratory. It had a very long run at pole position, ranking no.1 since November 2004.

IBM at the top and thereabouts is the normal scheme of things in the TOP500 list. Upsetting the natural order, is a new entry at number 4, the University of Texas's Ranger (326 teraflop/s) system built by Sun. It's been a long time since Sun has ranked so prominently. But then this time around it's a topsy-turvy TOP500, with the compilers noting "the largest turnover rate in [its] 16-year history". The last system on the list, they say "would have been listed at position 200 in the previous TOP500 just six months ago".

What else? Intel-powered systems grew in dominance, now featuring in 75 per cent of installations, up from 70 per cent in November. Quad core processors are flooding the supercomputer world, with 283 systems using them.

The US is the daddy of the supercomputing world (257 installations), with Europe (184 ) and Asia (48) lagging far behind. US vendors also dominate. IBM has most entries - 210 systems (42 per cent) - over Hewlett Packard with 183 systems (36.6 per cent). Dell (5.4), SGI (4.4) and Cray (3.2) bring up the rear.

By system count, HP is increasing market share. Six months ago it had 166 systems, while IBM had 232 systems. When it comes to performance, IBM is streets ahead. Someone else can do the maths, but IBM's Roadrunner no doubt helped the company increase its lead by this measure to 48 per cent of installed total performance (up from 45). HP eased a little to 22.4 per cent, down from 23 per cent last time around.

TOP500 compilers have introduced a new metric with today's rankings - energy efficiency. This is very modish, but we suspect that governments relying on compute power for nuclear bomb simulations, say, are unfussed with the electricity bill that their taxpayers must bankroll. ®