On 11 Jan 2017, at 18:34, Steve Johnson <scj@yaccman.com> wrote:

IMHO, hardware has left software in the dust.  I figured out that if cars had evolved since 1970 at the same rate as computer memory, we could now buy 1,000 Tesla Model S's for a penny, and each would have a top speed of 60,000 MPH.  This is roughly a factor of a trillion in less than 50 years.

This doesn't mean that the process will continue: eventually you hit physics limits ('engineering' is really a better term, but it has been so degraded by 'software engineering' that I don't like to use it).  Obviously we've already hit those limits for clock speed (when?) and we might be close to them for single-threaded performance in general: the current big (HPC big) machine where I work has both lower clock speed than the previous  one and observed lower single-threaded performance as well, although its a lot more scalable, at least in theory.  The previous one was POWER, and was I think the slightly mad very-high-clock-speed POWER chip, which might turn out to be the high-water-mark of single-threaded performance; the current one is x86.

Obviously for a while parallel scaling will mean things continue, but that crashes into other limits as well.

I think we've all lived in a wonderful time where it seemed like various exponential processes could continue for ever: they can't.

--tim