"At more than one quadrillion floating point operations per second..." - how fast is that when cracking typical passwords or mining bitcoins? If we have an encrypted drive, how long would it take to find the passphrase with it?
Bitcoin uses double SHA256 which is all integer operations, so that's not directly comparable to flops.
As far as I know most passwords hashes are also integer operations.
The cell processor in the ps3, despite being optimized for floating point ops, can do about 22.23 Mh/s. Assuming each of the 12,960 PowerXCell 8is in Roadrunner can do the same: 12960 * 23.23 ~= 288100 Mh/s which would earn you about 21.6 BTC/day at the current difficulty. That's about $2000/day at current prices.
The PowerXCells also have 8 SPUs vs 6 in the ps3, so they are potentially 25% faster.
For bitcoin mining you probably want to use Titan's 56k GPUs. I've run jobs at full scale on Titan, sometimes I forget it can be pretty cool to be in HPC!
I'm also interested in what language and tooling you're using, plus the scientific field. Depending on what you do, you might be interested in [1]. It's my current project dealing with better tooling for CPU and GPU compatible Fortran code.
might be kind of interesting to do an IamA on reddit. I'd like to hear more about what it's like to work in HPCs -- even simply considering how to build that kind of processing and how to think in terms of jobs that take real time to complete.
