The article's comparison is invalid - in HPC computing speed is as much about the network infrastructure as it is the raw number of cores; simulations and graph-processing require interaction between the processing elements. The scores on the Top500 reflect this. In an embarrassingly-parallel application such as bitcoin mining, their peak performance is far higher.
In fact, the theoretical peak of Titan's 19k GPUs would be around 90 single-precision petaflops, comfortably higher than the estimated peak of 2 million reasonably recent x86 processors in Google's data centers (unlikely to be top-of-the-range number crunchers).
I've worked in HPC with a variety of actors for over a decade; I am in no doubt that classified machines exist with more power than Titan and Sequoia (#1, #2), which together make up most of the computing power in the top500 (it follows a power distribution, appropriately).
An exaflop is still a really, really big number though. I can hazard a few guesses at non-public machines in the US that would reach or beat Titan. Perhaps the US Govt commands an exaflop of power spread amongst several agencies, but I wouldn't place any bets on it.
That the bitcoin mining network has reached this scale is both astounding and depressing. That's an awful lot of computing power going to waste.
It's in the design of bitcoin -- its network power must grow enough to defend against attacks on the increasingly lucurative bitcoin market. The bigger the market, the more expensive attacks are worthwhile. Conversely, the hardware driving bitcoin could be part of its valuation.
The hardware working in the bitcoin network is it's capital backing. The more hardware backs it, the more resilient bitcoin is to attacks.
If we valued one bitcoin at $1 million today, we would have a problem, because the hardware required to attack the network would be much cheaper than the potential gains of an attack.
It is not capital backing in that I cannot exchange a bit coin for a computer. Agree it may provide an upper bound on the value of bitcoin, but not a lower bound.
In fact, the theoretical peak of Titan's 19k GPUs would be around 90 single-precision petaflops, comfortably higher than the estimated peak of 2 million reasonably recent x86 processors in Google's data centers (unlikely to be top-of-the-range number crunchers).
I've worked in HPC with a variety of actors for over a decade; I am in no doubt that classified machines exist with more power than Titan and Sequoia (#1, #2), which together make up most of the computing power in the top500 (it follows a power distribution, appropriately).
An exaflop is still a really, really big number though. I can hazard a few guesses at non-public machines in the US that would reach or beat Titan. Perhaps the US Govt commands an exaflop of power spread amongst several agencies, but I wouldn't place any bets on it.
That the bitcoin mining network has reached this scale is both astounding and depressing. That's an awful lot of computing power going to waste.