The fastest supercomputer in the world, the Los Alamos National Laboratory’s IBM Roadrunner, can perform 1,000 trillion operations per second, which computer scientists call the petaflop scale. Getting up to the next level, the exaflop scale, which is three orders of magnitude faster, will require integrating more optical components to save on power consumption, Kash said. (Laser scientists at the conference are also looking towards the exascale, as I reported on Wednesday.)
Melinda Rose of photonics.com reported on Kash’s talk, which he stated represented his personal views and not those of IBM:
Because a 10x increase in performance means the machine will consume double the power, to make future supercomputers feasible to build and to operate optics will need to be more widely used he said. In 2008 a 1-petaflop computer cost $150 million to build and consumes 2.5 MW of power. Using the same technology, by 2020 a 1 exaflop machine would cost $500 million to build and consume 20 MW of power.
Kash gave a timeline that would find optics replacing electrical backplanes by 2012 and replacing electrical printed circuit boards by 2016. In 2020, optics could be directly on the chip. In a less aggressive scenario, by 2020 all off-chip communications need to be optical, he said.
But for that to happen, to get optics up to millions of units in 2010, the price needs to drop to about $1 per Gb/s, he said. Today, Gb/s processing costs about $10.