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The computers are fast, but you don't know it

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Re: The computers are fast, but you don't know it

#431

Post by geysersam »

tylerchr wrote: post #320
geysersam wrote: post #189

Earlier quoted context omitted.

Shitty performance certainly is bad, but it is not an externality like emissions into the atmosphere. The fundamental difference is that the customer (and only the customer) is harmed by bad performance, while emissions harms everyone.

I'm not so sure. Emissions don't harm everyone instantly; they affect people disproportionately and only impact everyone over time as the effects accumulate. Sure, maybe bad performance only affects the customer initially, but can't you help but wonder what the cumulative opportunity cost of bad performance on civilization has been? The predominant perception among nontechnical people is that computers are fundamenta…

Externalities is a concept in economic theory. It shows how net negative behaviour occurs, even when all actors act perfectly rational and have perfect information (while optimizing for their own gain). Bad software does simply not map to this concept in the same way environmental damage does. In your example people use bad software, against their interest, despite better alternatives.

Re: The computers are fast, but you don't know it

#432

Post by CMCDragonkai »

somenameforme wrote: post #427
generalizations wrote: post #108

Earlier quoted context omitted.

I ran across an animation once that showed graphically the time it takes light to travel between the planets and the sun. It's weird, but light doesn't seem that fast anymore.

The much more remarkable thing is to consider that that speed of light is also the speed of causality itself. It takes light from the sun about 8 minutes to reach Earth. If the sun suddenly disappeared, we'd still see it shining brightly in the sky, and the Earth would continue revolving around it - all for another 8 minutes until reality finally caught up to us. So we're already computing at a rate on the verge of t…

Is the speed of light really the speed of causality? Would the effect of gravity (the lack of) affect Earth earlier than us perceiving the lack of light.

Re: The computers are fast, but you don't know it

#433

Post by p1esk »

easytiger wrote: post #405
p1esk wrote: post #140

Earlier quoted context omitted.

Which “accelerated” libraries for matrix operations are you talking about? Try writing a matmul operation in C++ and profile it against the same thing done in Numpy/Pytorch/TensorFlow/Jax. You’ll be surprised.

Doesn't numpy use a natively compiled Fortran or c library for that? https://github.com/numpy/numpy/blob/main/numpy/core/src/mult...

Why should I care what Numpy is written in? All I see is Python.

Re: The computers are fast, but you don't know it

#434

Post by d110af5ccf »

CMCDragonkai wrote: post #432
somenameforme wrote: post #427

Earlier quoted context omitted.

The much more remarkable thing is to consider that that speed of light is also the speed of causality itself. It takes light from the sun about 8 minutes to reach Earth. If the sun suddenly disappeared, we'd still see it shining brightly in the sky, and the Earth would continue revolving around it - all for another 8 minutes until reality finally caught up to us. So we're already computing at a rate on the verge of t…

Is the speed of light really the speed of causality? Would the effect of gravity (the lack of) affect Earth earlier than us perceiving the lack of light.

Nope. All physical effects are bounded by the speed of light. (As far as anyone knows, anyway.)

The only weird one is quantum entanglement, but even then information transfer doesn't travel faster than light and that's about all I know on that subject.

Re: The computers are fast, but you don't know it

#435

Post by e63f67dd-065b »

CMCDragonkai wrote: post #432
somenameforme wrote: post #427

Earlier quoted context omitted.

The much more remarkable thing is to consider that that speed of light is also the speed of causality itself. It takes light from the sun about 8 minutes to reach Earth. If the sun suddenly disappeared, we'd still see it shining brightly in the sky, and the Earth would continue revolving around it - all for another 8 minutes until reality finally caught up to us. So we're already computing at a rate on the verge of t…

Is the speed of light really the speed of causality? Would the effect of gravity (the lack of) affect Earth earlier than us perceiving the lack of light.

The speed of light is the speed of information propagation. Information about the sun disappearing would only reach earth at after c/1AU.

Re: The computers are fast, but you don't know it

#436

Post by kllrnohj »

nyanpasu64 wrote: post #366
munificent wrote: post #68

Earlier quoted context omitted.

I agree 100%. I wish every software engineer would spent at least a little time writing some programs in bare C and running them to get a feel for how fast a native executable can start up and run. It is breathtaking if you're used to running scripting languages and VMs. Related anecdote: My blog used to be written using Jekyll with Pygments for syntax highlighting. As the number of posts increased, it got closer and…

I wish C++ compilers written in C++ were blazing fast too.

They are. They've just chosen to spend all their speed gains on more optimization passes and static analysis, to produce ever faster outputs than to produce an output faster.

Re: The computers are fast, but you don't know it

#437

Post by pjmlp »

jerf wrote: post #6

I've been lightly banging the drum the last few years that a lot of programmers don't seem to understand how fast computers are, and often ship code that is just miserably slower than it needs to be, like the code in this article, because they simply don't realize that their code ought to be much, much faster. There's still a lot of very early-2000s ideas of how fast computers are floating around. I've wondered how m…

I learned that lesson with Tcl and Perl, 20 years ago.

If there isn't a compiler in the box (JIT or AOT), I won't be using language XYZ, unless forced by customers.

The only reason I use Python is for UNIX scripting.

Re: The computers are fast, but you don't know it

#439

Post by pjmlp »

michaelsshaw wrote: post #156
bb88 wrote: post #151

Earlier quoted context omitted.

Please don't write programs in go. Sure it looks awesome on the surface but it's a nightmare when you get a null pointer panic in a 3rd party library. Instead use Rust. See here for more info: https://getstream.io/blog/fixing-the-billion-dollar-mistake-...

Nothing wrong with any of these languages, especially C. It's been around since the early 70s and is not going anywhere. There's a very good reason it (and to an extent C++) is still is the default language for doing a lot of things since everyone understands it.

One reason is historical baggage and sinergy.

It is easier to just pick an existing library and deal with security flaws, than trying to ramp up an ecosystem from scratch, unless one has the backing of a multinational pumping up development.

Re: The computers are fast, but you don't know it

#440

Post by reacharavindh »

dragontamer wrote: post #60
forinti wrote: post #22

On a 3GHz CPU, one clock cycle is enough time for light to travel only 10cm. If you hold up a sign with, say, a multiplication, a CPU will produce the result before light reaches a person a few metres away.

> If you hold up a sign with, say, a multiplication, a CPU will produce the result before light reaches a person a few metres away. The latency on multiplication (register input to register output) is 5-clock ticks, and many computers are 4GHz or 5GHz these days. 5-clock cycles at 5GHz is 1ns, which is 30-centimeters of light travel. If we include L1 cache read and L1 cache write, IIRC its 4 clock cycles for read + 4…

This reminds me of that “todo” I wrote for myself a long time ago. These days processors come with bigger L1,L2, and L3 caches. Would it be possible for a program that works on a tiny bit of data(few KB) to load it all up in the cache and provide ultimate response times?!

Are there any directives to the Operating System to say - “here keep this data in the fastest accessible L[1,2,3] please”?

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