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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

#121

Post by edbaskerville »

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.

The thing that did for me is realizing that people on opposite sides of the United States can't play music together if it requires any rhythmic coordination, even with a true speed-of-light signal with no other sources of latency.

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

#122

Post by morelisp »

google234123 wrote: post #110
grishka wrote: post #90

Earlier quoted context omitted.

Huh, but then I'm pretty sure that there are some paths inside the CPU die that are long enough that speed of light is a consideration at these frequencies. Must require a lot of smart people to design these things, yet it only takes a bunch of junior developers to bog them down.

I say we ban all junior devs.

Easier to raise the speed of light.

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

#123

Post by momojo »

remuskaos wrote: post #105
bbojan wrote: post #18

Earlier quoted context omitted.

I recently ported some very simple combinatorial code from Python to Rust. I was expecting around 100x speed up. I was surprised when the code ended running only 14 times faster.

Did you use python specific functions like list comprehensions, or "classic" for/while loops? Because I've found the former to be surprisingly fast, while naive for loops are incredibly slow in python.

Aren't most of the python primitives implemented in C?

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

#124

Post by radicalbyte »

dataflow wrote: post #97
Gibbon1 wrote: post #74

Earlier quoted context omitted.

C# is faster than python and as easy to use.

As nice as it is, C# is definitely not as easy to use as Python.

If you're using an IDE (Rider or Visual Studio) and avoid the Enterprise frameworks, then it's much easier to use than Python. Tooling makes a huge difference, no more digging through the sometimes flakey Python documentation and cursing compatibility issues with random dependencies not supporting Apple Silicon.

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

#125

Post by MiddleEndian »

grishka wrote: post #77
marcosdumay wrote: post #19

Earlier quoted context omitted.

It's not only a matter of 750ms instead of 200ms. I'm astonished every time I open some tool like Visual Studio, SAP Power Designer, or Libre Office that can stay for the most part of a minute on its loading screen. What do those tools even do for that long? They can read enough data from the disk to overflow my computer's main memory a few times during it.

I remember a video of a guy running an old version of Visual C++ on an equally old version of Windows, in a VM on modern hardware, to try Windows development "the old way". It took about one frame to launch. One. Frame. By the way, Apple isn't much better. Xcode takes around 15 seconds to launch on an M1 Max. edit: probably this video https://youtu.be/j_4iTovYJtc?t=282

But imagine if Visual C++ was written entirely in Electron instead! Wouldn't THAT be sweet?

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

#126

Post by pjvsvsrtrxc »

tester756 wrote: post #93
jcelerier wrote: post #73

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. Conversely when 99.9% of the software you use in your daily life is blazing fast C / C++, having to do anything in other stacks is a complete exer…

Is performance inversely proportional to dev experience? because what you wrote could be said about using C++ in the context of dev experience 10 compilers, IDEs, debuggers, package managers and at the end of the day LLVM compiles 30min and uses tens of GBs of RAM on average hardware I don't believe that this is the best we can get.

Huh?

"10 compilers, IDEs, debuggers, package managers" what are you talking about? (Virtually) No one uses ten different tools to build one application. I don't even know of any C++-specific package managers, although I do know of language-specific package managers for... oh, right, most scripting languages. And an IDE includes a compiler and a debugger, that's what makes it an IDE instead of a text editor.

"and at the end of the day LLVM compiles 30min and uses tens of GBs of RAM on average hardware" sure, if you're compiling something enormous and bloated... I'm not sure why you think that's an argument against debloating?

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

#127

Post by zasdffaa »

Yajirobe wrote: post #100
zasdffaa wrote: post #27

Earlier quoted context omitted.

Get beyond a certain size of python program and you lose dev time. IOW you lose both. It's not a huge size either.

Like... youtube?

could you elaborate please - is all of youtube including the streaming, all python?

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

#128

Post by yoyohello13 »

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 felt this pretty viscerally recently. I did Advent of Code 2021 in python last year. My day job is programming in Python so I didn't really think about the execution speed of my solutions much.

As a fun exercise this year I've been doing Advent of Code 2020 in C, and my god it's crazy how much faster my solutions seem to execute. These are just little toy problems, but even still the speed difference is night and day.

Although, I still find Python much easier to read and maintain, but that may just be I'm more experienced with the language.

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

#129

Post by SV_BubbleTime »

babypuncher wrote: post #111
Guest19023892 wrote: post #26

Earlier quoted context omitted.

I upgraded a desktop machine the last time I visited my family. It was a Windows 7 computer that was at least 10 years old with 4GB of ram. They wanted to use it online for basic web browsing, so I thought I'd install Windows 10 for security reasons and drop in a modern SSD to upgrade the old 7200rpm drive to make it more snappy. Well, it felt slower after the "upgrade". Clicking the start menu and opening something…

Throw in more RAM and Windows 10 will likely feel snappier than Windows 7 did. It's probable the old Windows 7 install was 32-bit while your fresh install of 10 would have defaulted to 64-bit. That combined with 10's naturally higher memory requirements means the system has less overhead to work with.

It’s all this, and I’m dealing with it today.

Mother I law bought a machine with 4GB of ram, which was fine before windows 10. Now it spends all day doing page/sysfile swap from its mechanical hard drive. Basically unusable.

So here in my pocket is an 8GB stick of DDR3 sodimm for later.

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

#130

Post by FirstLvR »

This is exactly what I was dealing last year, some particular costumer came to meeting with the idea developers has to be aware of making the code Inclusive and sustainable... We told them that we must set priorities on the performance and the literal result from the operation (a transaction development from an integration)

Nothing really happened at the end but it's a funny history in the office

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