Re:Ask HN: What comes after we hit the 16nm barrier?
by jonsen on Monday June 01, 2009 @07:44AM
(#635916)
The neuron runs at just 100 Hz, yes, but the brain is not a synchronously clocked machine. How much information processing capacity is due to the timing of spikes? How fine grained is its time sensitivity? 1ms? 1ns? 1µs? 1ps? ...
Re:Ask HN: What comes after we hit the 16nm barrier?
by fauigerzigerk on Monday June 01, 2009 @07:36AM
(#635910)
If it is as you say, all the better. It means that increased processing power could be achieved by making better use of the parallel hardware we already have. Still, I contend that using parallelism is key in some shape or form.
I cannot say much about transistor density issues as I'm not competent in that area. I read that IBM is experimenting with nano technology in order to create much more dense hardware that uses very little energy. I have no idea how far out that sort of approach is.
The numbers I've seen suggest that it's total 'processing power' is only on the order of a few hundred teraflops - and we already have plenty of clusters bigger than that. I know that floating point operations per second is a crappy metric but consider that a neuron can only spike about 100 times per second (i.e., the brain runs at 100 Hz) - even billions of neurons put together just aren't that powerful in terms of hardware.
Software, not hardware, is already the limiting reagent to 'smart' computers.
Everyone says 'massive parallelism' is the answer. But once transistor density plateaus the only way to add more cores (i.e., add more parallelism) will be to make CPUs physically bigger (or make each core 'weaker'). Making each core 'weaker' adds very little net benefit (2 * 100 = 20 * 10) and having physically larger CPUs isn't really practical beyond a point ...