Supercomputer quietly puts U.S. weather resources back on top

Supercomputer quietly puts U.S. weather resources back on top
usatoday.com

Weather forecasting accuracy is still constrained by both the available observations and the ability to run the forecast models. This new supercomputer won't be nearly enough to process all the new data that will arrive in the next few years, so the pendulum will swing back to the bottleneck being computing power soon enough. I think the most exciting things will happen over the next 5-10 years, as we end up with another 2-3 order of magnitude increase in the available observations to the models and we'll build new supercomputers to process them. I bet we can get incredible improvements, things like reliable 2-week weather forecasts.

high fidelity weather modelling algorithms are highly constrained by node-to-node communication latency. So their supercomputer probably has some networked-direct-memory-access or another non-standard setup tuned toward passing data between adjacent nodes quickly.

The main differentiation vs a standard datacenter is low-latency high-throughput interconnects, often with a specific or reconfigurable topology. Something like InfiniBand, where you can ensure very consistent, very favorable bounds on your latency and throughput. So think of it as being a "custom installation" or "custom cluster" instead.

Nowadays there really are only a few real choices left in high-performance computing hardware: CPU vs GPU, processor architecture (eg POWER vs x86), and interconnection. Everything else is more or less irrelevant.

I have to admit though, I've always wanted to see what you'd get if you built a Cray-2 with GPU chips (eg Pascal) or Xeon Phi as processing modules. The sheer density of chips Cray managed to cram in that case is impressive.