OT: This Swift thing

[Rustom Mody]

I am bewildered by this argument...

[Heck Ive recently learnt that using ellipses is an easy way to 
produce literature... So there...]

On Thursday, June 12, 2014 2:36:50 PM UTC+5:30, Steven D'Aprano wrote:

> It is my contention that, had Intel and AMD spent the last few decades 
> optimizing for power consumption rather than speed, we probably could run 
> a server off, well, perhaps not a watch battery, but surely a factor of 
> 100 improvement in efficiency isn't unreasonable given that we're just 
> moving a picogram of electrons around?

This is fine and right.
I personally would pay more if my PCs/laptops etc were quieter/efficient-er.
So we agree... upto here!


> On Thu, 12 Jun 2014 12:16:08 +1000, Chris Angelico wrote:

> > On Thu, Jun 12, 2014 at 12:08 PM, Steven D'Aprano wrote:
> >> I'm just pointing out that our computational technology uses over a
> >> million times more energy than the theoretical minimum, and therefore
> >> there is a lot of room for efficiency gains without sacrificing
> >> computer power. I never imagined that such viewpoint would turn out to
> >> be so controversial.
> > The way I understand it, you're citing an extremely theoretical minimum,
> > in the same way that one can point out that we're a long way from
> > maximum entropy in a flash memory chip, so it ought to be possible to
> > pack a lot more data onto a USB stick. 

> Um, yes? 

> Hands up anyone who thinks that today's generation of USB sticks will be 
> the highest capacity ever, that all progress in packing more memory into 
> a thumb drive (or the same memory into a smaller drive) will cease 
> effective immediately?

> Anyone?

> > The laws of physics tend to put
> > boundaries that are ridiculously far from where we actually work - I
> > think most roads have speed limits that run a fairly long way short of
> > c.

> "186,000 miles per second: not just a good idea, it's the law"

> There's no *law of physics* that says cars can only travel at the speeds 
> they do. Compare how fast a typical racing car goes with the typical 
> 60kph speed limit in suburban Melbourne. Now compare how fast the 
> Hennessey Venom GT goes to that speed limit.

> http://www.autosaur.com/fastest-car-in-the-world/?PageSpeed=noscript

Now you (or I) are getting completely confused.

If you are saying that the Hennessey Venom (HV) is better than some
standard vanilla Ford/Toyota (FT) based on the above, thats ok.

In equations:
maxspeed(HV) = 250 mph
maxspeed(FT) = 150 mph
so HV is better than FT.

Ok...

But from your earlier statements you seem to be saying its better
because:
250 mph is closer to 186,000 mps (= 670 million mph) than 150 mph

Factually this is a correct statement.

Pragmatically this is as nonsensical as comparing a mile and a
kilogram.


> Speed limits for human-piloted ground-based transport ("cars") are more 
> based on social and biological factors than engineering ones. Similarly, 
> there are biological factors that force keyboards to be a minimum size. 
> We probably could build a keyboard where the keys were 0.1mm square, but 
> what would be the point? Who could use it? Those social and biological 
> factors don't apply to computing efficiency, so it's only *engineering* 
> factors that prevent us from being able to run your server off a watch 
> battery, not the laws of physics.

As best as I can see you are confused about the difference between
science and engineering.

Saying one car is better engineered than another on direct comparison
(150mph<250mph) is ok

Saying one car is better than another because of relation to physics
limits (c-150>c-250) is confusing science and engineering.

Likewise saying AMD and Intel should have done more due diligence to
their clients (and the planet) by considerging energy efficiency is right 
and I (strongly) agree.

But compare their products' realized efficiency with theoretical limits like
Landauers is a type-wrong statement