Troubled Times Ahead for Supercomputers

The Green 500 is more than a concern for global warming. It is also a measure of scalability due to heat dissipation and power supply concerns. The difficulty of achieving a human-brain sized supercomputer will be more about energy efficiency than actual computational ability.

Actually a problem few people are aware of and are working on is the problem of IO. While there is the old quip of supercomputers being devices to turn CPU bound problems into IO bound problems, it is a real problem to keep a well tuned HPC application on a supercomputer fed with data. And even if you are lucky and have an application with with a small input dataset, it gets hard to write snapshots (e.g. for checkpointing) once you go beyond 100000 CPUs or so. And at that point you really want checkpointing, because the failure probabilty of the nodes rears it's ugly head.

>The ratio can now be as much as 1:100, so a supercomputer is forced to spend the vast majority of its time moving data to and from memory. This is spurring the adoption of data-tiering hardware and software that try to maximize CPU effectiveness by storing frequently accessed data in high-speed tiers such as solid-state drive

Err... this isn't new, wouldn't the high speed tiers be processor registers and cache and we've been doing this for over 30 years?

Trying to figure out why the menu is borked on the iPhone. If you reload the article in landscape it works. Sorry!