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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

#241

Post by etaioinshrdlu »

pjvsvsrtrxc wrote: post #144
etaioinshrdlu wrote: post #17

My entire career, we never optimize code as well as we can, we optimize as well as we need to. Obviously the result is that computer performance is only "just okay" despite the hardware being capable of much more. This pattern repeats itself across the industry over decades without changing much.

The problem is that performance for most common tasks that people do (f.e. browsing the web, opening a word processor, hell even opening an IM app) has gone from "just okay" to "bad" over the past couple of decades despite our computers getting many times more powerful across every possible dimension (from instructions-per-clock to clock-rate to cache-size to memory-speed to memory-size to ...) For all this decreased…

I think a lot of this is actually somewhat misremembering how slow computers used to be. We used to use spinning hard disks, and we were so often waiting for them to open programs.

Thinking about it some more, the iPhone and iPad actually comes to mind as devices that perform well and are practically always snappy.

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

#242

Post by BeFlatXIII »

LoveMortuus wrote: post #202
kossTKR wrote: post #132

Earlier quoted context omitted.

I hope one day latency in general will be "back to normal". I still remember how fast console based computing, an old gameboy or a 90's macintosh would be - click a button and stuff would show up instantly. There was a tactility present with computers that's gone today. Today everything feels sluggish - just writing this comment on my $3000 Macbook Pro and i can feel the latency, sometimes there's even small pauses.…

May I ask if you're using the M1 based MacBook or the Intel one? I'm asking because I've been thinking of getting a MacBook Air in the future with the intent to use it for writing.

I have an M1 Air right I'm typing on right now and have not had any sluggishness concerns besides when switching between Spaces. Even that is more of a visual stutter instead of actually lagging to the point the animation takes longer than usual. This is the first thin & light computer I've owned that I'm 100% happy with its performance.

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

#243

Post by _gabe_ »

throwaway894345 wrote: post #194
KronisLV wrote: post #164

Earlier quoted context omitted.

C and C++ both have excellent library support, perhaps the best interop of any language out there and platform support that cannot be beat. That said, they're also challenging to use for the "average" (median) developer who'd end up creating code that is error-prone and would probably have memory leaks sooner or later. Thus, unless you have a good reason (of which, admittedly, there are plenty) to use C or C++, somet…

> That said, they're also challenging to use for the "average" (median) developer who'd end up creating code that is error-prone and would probably have memory leaks sooner or later. Many of the most highly credentialed, veteran C developers have said they can't write secure C code. Food for thought. > Go is a decent choice, because of a fairly shallow learning curve and not too much complexity, while having good lib…

> secure C code.

There is unsecure code hidden in every project that uses any programming language ;)

I get what you're saying here, you're specifically talking about security vulnerabilities from memory related errors. I honestly wonder how many of these security vulnerabilities are truly issues that never would have come up in a more "secure" language like Java, or if the vulnerabilities would have just surfaced in a different manner.

In other words, we're constantly told C and C++ are unsafe languages they should never be used and blah blah blah. How much of this is because of the fact that C has been around since the 1970s, so its had a lot more time to rack up large apps with security vulnerabilities, whereas most of the new recommended languages to replace C and C++ have been around since the late 90s. In another 20 years will we be saying the same thing about java that people say about C and C++? And will we be telling people to switch to the latest and greatest because Java is "unsafe"? Are these errors due to the language, or is it because we will always have attackers looking for vulnerabilities that will always exist because programmers are fallible and write buggy code?

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

#244

Post by rubyskills »

gpm wrote: post #161
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.

This is because numpy and friends are really good at matmul's. As soon as you step out of the happy path and need to do any calculation that isn't at least n^2 work for every single python call you are looking at order of magnitude speed differences. Years ago now (so I'm a bit fuzzy on the details) a friend asked me to help optimize some python code that took a few days to do one job. I got something like a 10x spee…

Have you tried porting the problem into postgres? Not all big data problems can be solved this way but I was surprised what a postgres database could do with 40 million rows of data.

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

#245

Post by eterm »

Jtsummers wrote: post #219
eterm wrote: post #165

Earlier quoted context omitted.

Here's a one liner in c# for that: Enumerable.Range(1,50).Where((x,i) => i % 4 == 0).Where(e => e % 3 == 0).Skip(1).Select(e => e+4) Okay, so you might consider that last e+4 cheating and against the spirit, but I couldn't be bothered to spend money upgrading my linqpad to support the latest .net with Enumerable.Chunk which makes taking two at a time easier for the first part. Edit: more in spirit: Enumerable.Range(1…

If I understand dataflow's example correctly you don't need the Select at the end: var x = Enumerable.Range(1,50) .Where((num, index) => num % 4 == 1 && index % 3 == 0) .Skip(2) .ToArray(); That computes the same thing as their Python snippet: [25,37,49]. Of course, what this is actually computing is whether the number is congruent to 1 modulo 4 and 3 so it was a weird example, but here's how you'd really want to wri…

You're right, the maths simplifies it a lot. I rushed out a one-liner without much analysis, and eventually come to the same conclusion.

There's no Range method that takes (start, stop, step) but it's trivial enough to write one, it's a single for loop and yield return statement.

We can even trigger the python users by doing it in one line ;)

    public static class CustomEnumerable { public static IEnumerable Range(int start, int stop, int step) {for (int i = start; i
Try writing your function definitions on one line in python!

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

#246

Post by Jtsummers »

dataflow wrote: post #229
Jtsummers wrote: post #219

Earlier quoted context omitted.

If I understand dataflow's example correctly you don't need the Select at the end: var x = Enumerable.Range(1,50) .Where((num, index) => num % 4 == 1 && index % 3 == 0) .Skip(2) .ToArray(); That computes the same thing as their Python snippet: [25,37,49]. Of course, what this is actually computing is whether the number is congruent to 1 modulo 4 and 3 so it was a weird example, but here's how you'd really want to wri…

> num % 12 > That enumerate wrapper was unnecessary. I'm surprised you didn't go all the way and just write x = [25, 37, 49] and tell me the rest of the code was unnecessary!

I mean, was it necessary? Your original Python expression was pretty obfuscated for such a simple calculation.

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

#247

Post by geysersam »

willis936 wrote: post #216
geysersam wrote: post #184

Earlier quoted context omitted.

Yes but what kind of comparison is that: 1. How often do you need to execute 1000 GUI instances? 2. How often do you need to print "hello world"? The right tool for the right job.

This is a discussion about computers being slow. As in a person asks a computer to do something and the human waits while the computer does it. So python isn't the right tool for any job that involves human interaction.

Nah that's too general. A lot of website/app backends use Django or Fastapi and they work fine. Many more use PHP, also not a language famed for extreme performance.

It depends on the application. Personally I wouldn't use Python for a GUI (because I'd use JS/TS).

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

#248

Post by shultays »

generalizations wrote: post #108
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.

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.

I feel like it is more like we cant comprehend how big and empty space is

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

#249

Post by andrewclunn »

How are we supposed to optimize coding languages, when the underlying hardware architecture keeps changing? I mean you don't write assembly anymore, you would right in the LLVM. Optimization was done because it was required. It will come back when complete commoditization of cpus occur. Enforcement of standards and consistent targets allow for high optimizations. Just see what people are able to do with outdated hardware in the demo and homebrew scene for old game consoles! We don't need better computers, but so long as we keep getting them, we will get unoptimized software, which will necessitate better computers. The vicious cycle of consumerism continues.

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

#250

Post by dataflow »

Jtsummers wrote: post #246
dataflow wrote: post #229

Earlier quoted context omitted.

> num % 12 > That enumerate wrapper was unnecessary. I'm surprised you didn't go all the way and just write x = [25, 37, 49] and tell me the rest of the code was unnecessary!

I mean, was it necessary? Your original Python expression was pretty obfuscated for such a simple calculation.

Are you actually suggesting I didn't realize I could've written x = [25, 37, 49], or what?

Surely the point of the example wasn't "find the optimal way to calculate that particular list of numbers"?

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