Moore's Switch

The authorSteven Pemberton, CWI, Amsterdam

1957: The first municipal computer (Norwich, UK)

The First Computer in Norwich

Just one of 21 cabinets making up the computer.

2015: The Raspberry Pi Zero

Raspberry Pi in Norwich The first computer so cheap that they gave it away on the cover of a magazine

How do they compare?

What do you think the relationship is between the speeds of the two computers?

How do they compare?

What do you think the relationship is between the speeds of the two computers?

The Raspberry Pi is about one million times faster...

How do they compare?

What do you think the relationship is between the speeds of the two computers?

The Raspberry Pi is about one million times faster...

Which means: If they had run the Elliot 24 hours a day for 10 years, it would have done the amount of computing you can do on a Raspberry Pi Zero in about 5 minutes!

Compare

So the Raspberry Pi is:

A factor of a million million.

A terabyte is a million million bytes: nowadays we talk in terms of very large numbers.

Want to guess how long a million million seconds is?

A million million seconds

Is 30,000 years...

In other words, a really big number...

Moore's Law

In fact a million million times improvement is about what you would expect from Moore's Law over 58 years.

Except: the Raspberry Pi is two million times smaller as well, so it is much better than even that.

Happy Birthday Moore's Law!

Moore's original graph

In 2015 Moore's Law turned 50 years old.

Or less prosaically: Moore's Law was 33⅓ iterations of itself old.

Reports of Moore's Law's death are greatly exaggerated

The first time I head that Moore's Law was nearly at an end was in 1977. From no less than Grace Hopper, at Manchester University.

Since then I have heard many times that it was close to its end, or even has already ended. There was a burst of such claims in 2015, which caused a wag to tweet:

"The number of press articles speculating the end of Moore's Law doubles every eighteen months."

A data point: The Raspberry Pi

As an excellent example, in February 2015, almost exactly three years after the announcement of the first version, version 2 of the Raspberry Pi computer was announced. Two Raspberry Pi's, both alike in dignity

Moore's Law

Computer speeds 1988-2016So Moore's Law has been doing its work, and computers have been getting exponentially faster.

In 1988 my laptop had a power of 800. My present one has a power of nearly 30M. That is 15 doublings!

More amazing still: my current mobile phone has a speed of almost 115M!

Exponential change

November 2006This is November 2006

Six years later, the cheapest 4GB stick cost €2.99.

What exponential growth really means

Often people don't understand the true effects of exponential growth.

A BBC reporter: "Your current PC is more powerful than the computer they had on board the first flight to the moon". True, but oh so wrong.

Paper

Take a piece of paper, divide it in two, and write this year's date in one half:

Paper

Divide the other half in two vertically; write the date 18 months ago in half:

Paper

Divide the remains in half, and write the date 18 months earlier:

Paper

Repeat until your pen is thicker than the space you have to divide in two:

This demonstrates that your current computer is more powerful than all other computers you have ever had put together (and way more powerful than the computer they had on board the first moonshot).

Let's go back to 1957

In the 50's, computers cost in the millions. Nearly no one bought them, nearly everyone leased them.

To rent time on a computer then would cost you of the order of $1000 per hour: several times the annual salary of a programmer!

When you leased a computer in those days, you would get programmers for free to go with it.

Compared to the cost of a computer, a programmer was almost free.

The design of programming languages

TypingIn the 50's the computer's time was expensive. A programmer would:

Why? Because it was much cheaper to let 3 people check it, than to let the computer discover the errors.

The design of programming languages

And so programming languages were designed around the needs of the computer, not the programmer.

It was much cheaper to let the programmer spend lots of time producing a program than to let the computer do some of the work for you.

Programming languages were designed so that you tell the computer exactly what to do, in its terms, not what you want to achieve in yours.

1968

A short ten years later, there was already talk of a software crisis.

Programs being written that weren't functional, and/or weren't delivered on time.

Back to now

It happened slowly, almost unnoticed, but nowadays we have the exact opposite position:

Compared to the cost of a programmer, a computer is almost free.

I call this Moore's Switch.

Moore's Switch

Moore's Switch illustrated
Relative costs of computers and programmers, 1957-2017

But, we are still programming in programming languages that are direct descendants of the languages designed in the 1950's!

We are still telling the computers what to do.

Declarative programming

A new way of programming: declarative programming.

This describes what you want to achieve, but not how to achieve it.

Let me give some examples.

The first declarative definition

Declarative approaches describe the solution space.

A classic example is when you learn in school that

The square root of a number n is the number r such that r × r = n

This doesn't tell you how to calculate the square root; but no problem, because we have machines to do that for us.

Procedural code

function f a: {
    x ← a
    x' ← (a + 1) ÷ 2
    epsilon ← 1.19209290e-07
    while abs(x − x') > epsilon × x: {
        x ← x'
        x' ← ((a ÷ x') + x') ÷ 2
    }
    return x'
}

What does 'Declarative programming' mean?

A Procedural Clock

A clock in C, 1000+ lines

1000 lines, almost all of it administrative. Only 2 or 3 lines have anything to do with telling the time.

And this was the smallest example I could find. The largest was more than 4000 lines.

A Declarative Clock

type clock = (h, m, s)
displayed as 
   circled(combined(hhand; mhand; shand; decor))
   shand = line(slength) rotated (s × 60)
   mhand = line(mlength) rotated (m × 60)
   hhand = line(hlength) rotated (h × 30 + m ÷ 2)
   decor = ...
   slength = ...
   ...
clock c
c.s = system:seconds mod 60
c.m = (system:seconds div 60) mod 60
c.h = (system:seconds div 3600) mod 24

A Running Declarative Clock

The Views System

XForms

XForms is a declarative system that lets you define applications. BBC Sport App

It is a W3C standard, and in worldwide use.

Example: 150 person years becomes 10!

A certain company makes one-off BIG machines (walk in): user interface is very demanding — traditionally needed 5 years, 30 people.

With XForms this became: 1 year, 10 people.

Do the sums. Assume one person costs 100k a year. Then this has gone from a 15M cost to a 1M cost. They have saved 14 million! (And 4 years)

Example: Insurance Industry

Manager: I want you to come back to me in 2 days with estimates of how long it will take your teams to make the application.

Example: Insurance Industry

Manager: I want you to come back to me in 2 days with estimates of how long it will take your teams to make the application.

[Two days later]

Programmer: I'll need 30 days to work out how long it will take to program it.

Example: Insurance Industry

Manager: I want you to come back to me in 2 days with estimates of how long it will take your teams to make the application.

[Two days later]

Programmer: I'll need 30 days to work out how long it will take to program it.

XFormser: I've already programmed it!

Example: NHS

The British National Health Service started a project for a health records system.

Example: NHS

The British National Health Service started a project for a health records system.

One person then created a system using XForms.

Conclusion

For historical reasons, present programming languages are at the wrong level of abstraction: they don't describe the problem, but only one particular solution to the problem.

Once project managers realise they can save 90% on programming costs, they will switch to declarative programming.

I believe that eventually everyone will be programming declaratively: less errors, more time, more productivity.

Declarative programming allows programmers to be ten times more productive: what you now write in a week, would take a morning; what now takes a month would take a couple of days.